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#20549 From: "girtab" <klhutch@...>
Date: Thu Nov 12, 2009 7:20 pm
Subject: Re: Go for the Megrez 110??? 		girtab
Offline Offline
Send Email Send Email
  
--- In William-Optics@yahoogroups.com, "bbcoltrane" <bbcoltrane@...> wrote:
>
> I've got a Megrez 90 that I'm pretty impressed with, but I've got an
> itch for more aperture. My budget is modest, but if I sell off a scope
> or two I may be able to up-size to the Megrez 110.
>

I have a Megrez 110 that I use to supply the wide field views I cannot get with
much larger telescopes. I bought it expecting to sell it quickly. Everyone sings
the praises of small refractors for this application but the 80mm achromat I had
been using previously always left me cold. The aperture difference between it
and my large scopes was just too great. It always left me with the feeling that
it showed me a decently wide view of nothing. Too little light grasp. I didn't
have high expectations for the Megrez, I just wanted to give the small scope
thing one good try before declaring it utterly worthless.

The Megrez 110 surprised me. Oh, it still lags behind badly for light grasp
compared to my main scopes but it gives me enough that for my tastes (and it is
a matter of taste) it is much more worth having and unpacking than an 80 mm. I
even had it out by itself at a dark sky site soon after I bought it and was
surprised by how much it would show on its own when it was the only thing you
had to rely on. It can't keep up with a big scope yet it can show you way more
than you would expect after years of looking through much bigger glass have
skewed your opinion of how much aperture is required to have fun.

The images I get don't show any obvious defects at all. Obviously my usage does
not put a premium on CA performance but my attempts to find any have been
unrewarding. That may vary from scope to scope however since the suppression of
CA in a doublet depends on a certain amount of luck. If the two pieces of glass
you have in your scope happen to match each other well you get near perfection.
If not, you could have some color. In most cases it will not be enough to bother
a visual observer, it will be enough to allow the purists to hound you to your
grave. I think the chief advantage of the more expensive glass is that it
tolerates more variation in the glass matching because its CA "null" is deeper.
It might give you a broader bandwidth too which is a concern for imaging, not so
much of a concern for visual work.

If I look at the diffraction pattern on my scope it is apparent that there is a
very slight collimation error. This could be corrected, I think, but for my
purposes it is not necessary to expend the effort. A Ronchi test on stars gives
me nice, straight bands. The dew shield on mine also slides down under its own
weight when pointed high in the sky. There is no adjustment for that other than
gluing on thicker felt strips to hold it in place by friction. The soft half of
some Velcro fasteners will probably do the job but I have not gotten around to
that yet. The gold ring on the telescope end of the shield screws into the
shield itself so you can remove the shield to get at the collimation screws or
add that Velcro by grabbing the ring and twisting the shield. The focuser has
its good points and its bad points. It is generally quite good, where it fails
is in supporting heavy visual accessories. The "eyepiece" clamping screws, the
focus position drag, and the rotational clamp are all slightly lacking for
binoviewing with heavy eyepieces and the porky Denkmeier BV or even just the
gigantic 28mm UWAN that came with the scope. The focus position drag at least is
adjustable.

Overall I am very pleased with mine even if it is not absolutely perfect. I
found that 30mm aperture difference was quite worthwhile for my viewing, I can't
say for sure that 20mm would be as worthwhile to you.

Ken

Reply | Forward | Messages in this Topic (7)
#20550 From: "josjaspers4635" <jos.jaspers@...>
Date: Sat Nov 14, 2009 10:13 am
Subject: FLT152 or 158 with Sbig STL11000M ccd camera 		josjaspers4635
Offline Offline
Send Email Send Email
  
Looking around for a good refractor for using together with an Sbig STL11000M
ccd camera. For the FLT-132 a good field flattener is available. However I do
understand that this flattener cannot be used on the FLT-152 or FLT-158
telescopes. Will the Sbig work on both 152 and 158 and give good results without
using this flattener. I guess it will give some coma in the corners of the
pictures. Or not?

Thanks

Jos jaspers

Reply | Forward | Messages in this Topic (1)
#20551 From: "timmytlx200" <timmyt101@...>
Date: Sat Nov 14, 2009 3:55 pm
Subject: New FLT 110mm DDG Triplet APO f/7 		timmytlx200
Offline Offline
Send Email Send Email
  
Hi Everyone...

I have the new FLT 110mm DDG Triplet APO f/7 with the Digital Display Gauge and
new style focuser (linear dual speed).  I bought it from William at the P.A.T.S.
show in Pasadena (#1 !!!)  Has anyone else take delivery yet?  My issue is that
the focuser racks out buttery smooth, but needs some occassional pressure (push)
to rack back in.  I'm guessing it's an adjustement, but I don't have a manual as
they were not ready at the time I bought the scope and there's not one online
yet.

I've also sent a message to William and will post his reply here.  Thanks.

Tim

Reply | Forward | Messages in this Topic (3)
#20552 From: Perry Holcomb <hpholcomb@...>
Date: Sat Nov 14, 2009 4:11 pm
Subject: Re: [William Optics] New FLT 110mm DDG Triplet APO f/7 		hpholcomb
Offline Offline
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Congratulations, Tim!

Sounds like the focuser tension needs tightening.

But I know nothing about the new focuser or its adjustments.

Perry

--- On Sat, 11/14/09, timmytlx200 <timmyt101@...> wrote:

From: timmytlx200 <timmyt101@...>
Subject: [William Optics] New FLT 110mm DDG Triplet APO f/7
To: William-Optics@yahoogroups.com
Date: Saturday, November 14, 2009, 10:55 AM

 

Hi Everyone...

I have the new FLT 110mm DDG Triplet APO f/7 with the Digital Display Gauge and new style focuser (linear dual speed). I bought it from William at the P.A.T.S. show in Pasadena (#1 !!!) Has anyone else take delivery yet? My issue is that the focuser racks out buttery smooth, but needs some occassional pressure (push) to rack back in. I'm guessing it's an adjustement, but I don't have a manual as they were not ready at the time I bought the scope and there's not one online yet.

I've also sent a message to William and will post his reply here. Thanks.

Tim



Reply | Forward | Messages in this Topic (3)
#20553 From: Mark Acker <markacker@...>
Date: Sat Nov 14, 2009 6:06 pm
Subject: Reaching focus on a Megrez 		markacker
Offline Offline
Send Email Send Email
 
I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
Any insights would be greatly appreciated.

Thank you for your thoughts,
Mark

Reply | Forward | Messages in this Topic (19)
#20554 From: "H P" <hpholcomb@...>
Date: Sat Nov 14, 2009 6:51 pm
Subject: Re: Reaching focus on a Megrez 		hpholcomb
Offline Offline
Send Email Send Email
  
Mark,

See the posts from Sander Pool in the use of his M110ED.  He's got a relatively
long train behind the focuser.

Perry

--- In William-Optics@yahoogroups.com, Mark Acker <markacker@...> wrote:
>
> I know this has been discussed several times in the past, but wow, I am having
a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc
and in order to reach focus, I have to have the focuser racked almost all the
way out and still need 2-2" extensions.  The only way I can parfocalize an EP is
to go straight into the second extension without the use of a diagonal.  I am
exploring other scope options at the moment, but I won't be making a change
immediately.
> The actual issue here is flexure being introduced by the need for 2
extensions.  Am I missing something here or is this a known thing with the
Megrez line?  Is there a single 4" extension to be had somewhere or is this some
sort of custom job for someone?
> Any insights would be greatly appreciated.
>
> Thank you for your thoughts,
> Mark
>

Reply | Forward | Messages in this Topic (19)
#20555 From: Mark Acker <markacker@...>
Date: Sat Nov 14, 2009 7:00 pm
Subject: Re: [William Optics] Re: Reaching focus on a Megrez 		markacker
Offline Offline
Send Email Send Email
 
Thanks Perry, I will look them up now.

--- On Sat, 11/14/09, H P <hpholcomb@...> wrote:

From: H P <hpholcomb@...>
Subject: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@yahoogroups.com
Date: Saturday, November 14, 2009, 12:51 PM

 

Mark,

See the posts from Sander Pool in the use of his M110ED. He's got a relatively long train behind the focuser.

Perry

--- In William-Optics@ yahoogroups. com, Mark Acker <markacker@. ..> wrote:
>
> I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
> The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
> Any insights would be greatly appreciated.
>
> Thank you for your thoughts,
> Mark
>


Reply | Forward | Messages in this Topic (19)
#20556 From: "notgnirramot" <notgnirra@...>
Date: Sun Nov 15, 2009 4:15 pm
Subject: Re: New FLT 110mm DDG Triplet APO f/7 		notgnirramot
Offline Offline
Send Email Send Email
  
Hi Tom,

Congrats on the new scope!  I have the Lite version of the FLT 110 and it also
has the 2.5" linear focuser, but without the digital display.  Mine has two
knobs on the bottom of the focuser, one locks the focuser and the other adjusts
the tension.  My manual does not cover the linear focuser, but they give a
warning about adjusting the tension on the 4" standard focuser.  I have followed
that advice.

"William Optics warranty does not cover damage to the focuser due to
inappropriate tension setting.

This focuser is designed to hold many pounds without problems.  If nonetheless
your setup requires additional tension adjustment, please use the tension allen
screw under the focuser.  I order to avoid sagging or denting of the focuser
steel reinforcement, it is necessary to adjust tension ONLY when the drawtube is
FULLY EXTENDED."

I'd run the focuser out all the way and then experiment with the knobs to see
which locks and which one adjusts the tension.  After determining which is
which, you can set the tension as required.

Good luck and enjoy that new scope.

Tom

--- In William-Optics@yahoogroups.com, "timmytlx200" <timmyt101@...> wrote:
>
> Hi Everyone...
>
> I have the new FLT 110mm DDG Triplet APO f/7 with the Digital Display Gauge
and new style focuser (linear dual speed).  I bought it from William at the
P.A.T.S. show in Pasadena (#1 !!!)  Has anyone else take delivery yet?  My issue
is that the focuser racks out buttery smooth, but needs some occassional
pressure (push) to rack back in.  I'm guessing it's an adjustement, but I don't
have a manual as they were not ready at the time I bought the scope and there's
not one online yet.
>
> I've also sent a message to William and will post his reply here.  Thanks.
>
> Tim
>

Reply | Forward | Messages in this Topic (3)
#20557 From: rbrederode
Date: Sun Nov 15, 2009 5:22 pm
Subject: [William Optics] Re: Reaching focus on a Megrez 		rbrederode
Offline Offline
  
Im relatively new to this (so may not know what Im talking about :-))...I have
the Megrez 72 and tried reaching focus with a Meade DSI and could not reach
focus until I inserted my 90 deg diagonal...and then hey presto...focus.

I was under the impression a diagonal simply took the strain off your neck...and
didnt effect focus, magnification, field of view etc...

Does anyone know why focus could be reached only with a diagonal?

Ray

--- In William-Optics@yahoogroups.com, Mark Acker <markacker@...> wrote:
>
> Thanks Perry, I will look them up now.
>
> --- On Sat, 11/14/09, H P <hpholcomb@...> wrote:
>
> From: H P <hpholcomb@...>
> Subject: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@yahoogroups.com
> Date: Saturday, November 14, 2009, 12:51 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
>       Mark,
>
>
>
> See the posts from Sander Pool in the use of his M110ED.  He's got a
relatively long train behind the focuser.
>
>
>
> Perry
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > I know this has been discussed several times in the past, but wow, I am
having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI
IIIc and in order to reach focus, I have to have the focuser racked almost all
the way out and still need 2-2" extensions.  The only way I can parfocalize an
EP is to go straight into the second extension without the use of a diagonal. 
I am exploring other scope options at the moment, but I won't be making a change
immediately.
>
> > The actual issue here is flexure being introduced by the need for 2
extensions.  Am I missing something here or is this a known thing with the
Megrez line?  Is there a single 4" extension to be had somewhere or is this
some sort of custom job for someone?
>
> > Any insights would be greatly appreciated.
>
> >
>
> > Thank you for your thoughts,
>
> > Mark
>
> >
>

Reply | Forward | Messages in this Topic (19)
#20558 From: "notgnirramot" <notgnirra@...>
Date: Sun Nov 15, 2009 5:42 pm
Subject: Photo of the Iris Nebula 		notgnirramot
Offline Offline
Send Email Send Email
  
Here is a photo of the Iris Nebula taken last Wednesday.  It looked like that
would be the only night to image without the moon for the next 10 days, and the
current rainy weather has proven that assumption out.  The conditions were
marginal with good transparency and very poor seeing.  I was able to collect 2
hours of exposures, after that the nebula had sunk too low for the seeing.  It
could certainly use more time.

I used the 2X Drizzle in DSS to make the stack.

Details are with the photo.

http://tinyurl.com/yke4kju

or

http://www.pbase.com/image/119399044

Comments are welcome.

Tom

Reply | Forward | Messages in this Topic (1)
#20559 From: Mark Acker <markacker@...>
Date: Sun Nov 15, 2009 8:02 pm
Subject: Re: [William Optics] Re: Reaching focus on a Megrez 		markacker
Offline Offline
Send Email Send Email
 
Certainly others more knowledgeable than me can speak to this, but with my DSI IIIc, I have 2 extensions in order to reach focus.  I don't want to use a diagonal with a camera, so the second extension is necessary.  My issue was flexure and balance, but I think I have those worked out now-be sure to lock down the focuser screw once focus is achieved to eliminate the flex problem with a train that long.
The only real inconvenience is parfocalizing an EP.  Without a diagonal, it's a bit of a neck breaker.  I'm sure there is a way around this, but I haven't spent much time yet.  The balance and flex were much more problematic.
I am actually looking at a different scope altogether now.  Having this much gear on the back in order to reach focus is just a little more inconvenient than I thought it would be when I got the scope.

--- On Sun, 11/15/09, rbrederode <no_reply@yahoogroups.com> wrote:

From: rbrederode <no_reply@yahoogroups.com>
Subject: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@yahoogroups.com
Date: Sunday, November 15, 2009, 11:22 AM

 


Im relatively new to this (so may not know what Im talking about :-))...I have the Megrez 72 and tried reaching focus with a Meade DSI and could not reach focus until I inserted my 90 deg diagonal...and then hey presto...focus.

I was under the impression a diagonal simply took the strain off your neck...and didnt effect focus, magnification, field of view etc...

Does anyone know why focus could be reached only with a diagonal?

Ray

--- In William-Optics@ yahoogroups. com, Mark Acker <markacker@. ..> wrote:
>
> Thanks Perry, I will look them up now.
>
> --- On Sat, 11/14/09, H P <hpholcomb@. ..> wrote:
>
> From: H P <hpholcomb@. ..>
> Subject: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@ yahoogroups. com
> Date: Saturday, November 14, 2009, 12:51 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
> Mark,
>
>
>
> See the posts from Sander Pool in the use of his M110ED. He's got a relatively long train behind the focuser.
>
>
>
> Perry
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
>
> > The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
>
> > Any insights would be greatly appreciated.
>
> >
>
> > Thank you for your thoughts,
>
> > Mark
>
> >
>


Reply | Forward | Messages in this Topic (19)
#20560 From: kupainter
Date: Mon Nov 16, 2009 3:26 am
Subject: Re: Reaching focus on a Megrez 		kupainter
Offline Offline
  
Hi Mark, I have a older Megrez 80 II ED triplet.  I use Starlight Xpress Cameras
(HX916 and SXVF-H9).  They both are 17 mm from the front of the camera to the
chip.  I could not reach focus with two 2" extension tubes.  These telescope
tubes are cut short so they can be used with a binoviewer.

I can reach focus with a 0.8x focal reducer.  This shortens the focal length and
allows me to reach focus  with one 2" extension tube.
This also gives a wider field of view at F5.6.

Lynn




--- In William-Optics@yahoogroups.com, Mark Acker <markacker@...> wrote:
>
> I know this has been discussed several times in the past, but wow, I am having
a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc
and in order to reach focus, I have to have the focuser racked almost all the
way out and still need 2-2" extensions.  The only way I can parfocalize an EP is
to go straight into the second extension without the use of a diagonal.  I am
exploring other scope options at the moment, but I won't be making a change
immediately.
> The actual issue here is flexure being introduced by the need for 2
extensions.  Am I missing something here or is this a known thing with the
Megrez line?  Is there a single 4" extension to be had somewhere or is this some
sort of custom job for someone?
> Any insights would be greatly appreciated.
>
> Thank you for your thoughts,
> Mark
>

Reply | Forward | Messages in this Topic (19)
#20561 From: Mark Acker <markacker@...>
Date: Mon Nov 16, 2009 4:17 am
Subject: Re: [William Optics] Re: Reaching focus on a Megrez 		markacker
Offline Offline
Send Email Send Email
 
Great info.  Did you use the WO FR?  Was this the II or III?

Thanks Lynn,
Mark

--- On Sun, 11/15/09, kupainter <no_reply@yahoogroups.com> wrote:

From: kupainter <no_reply@yahoogroups.com>
Subject: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@yahoogroups.com
Date: Sunday, November 15, 2009, 9:26 PM

 


Hi Mark, I have a older Megrez 80 II ED triplet. I use Starlight Xpress Cameras (HX916 and SXVF-H9). They both are 17 mm from the front of the camera to the chip. I could not reach focus with two 2" extension tubes. These telescope tubes are cut short so they can be used with a binoviewer.

I can reach focus with a 0.8x focal reducer. This shortens the focal length and allows me to reach focus with one 2" extension tube.
This also gives a wider field of view at F5.6.

Lynn

--- In William-Optics@ yahoogroups. com, Mark Acker <markacker@. ..> wrote:
>
> I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
> The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
> Any insights would be greatly appreciated.
>
> Thank you for your thoughts,
> Mark
>


Reply | Forward | Messages in this Topic (19)
#20562 From: "jill g" <garyrmck@...>
Date: Tue Nov 17, 2009 9:00 am
Subject: Zenithstar 80 11 ED field flatness? 		garyrmck
Offline Offline
Send Email Send Email
  
Hi,
I'm looking at a Zenithstar 80 11 ed to use for imaging purposes. Can anyone
tell me if the field is flat enough to use with an APS sized sensor (QHY8)
without having to crop the field? Alternatively is there a definitive field
flattener that will correct any curvature. William optics reducer/correctors
seem to have had very mixed reception, and some appear to be no longer
available. Are ther any others that are reasonably priced that will serve the
purpose?

cheers
Gary

Reply | Forward | Messages in this Topic (1)
#20563 From: kupainter
Date: Wed Nov 18, 2009 1:36 am
Subject: [William Optics] Re: Reaching focus on a Megrez 		kupainter
Offline Offline
  
Mark, it is the older version. The one that WO first came out with. I guess you
would call it the I. I have the II, but I use that one on my WO66 so I can get
it to come to focus with a SXV guide camera. I think any 0.8x reducer would work
for focus.  The II and III give a flatter field for larger chips. Some prefer
the TeleVue.

I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x
Reducer/Corrector with a Astro Tech AT111ED.  For the same reason. To bring to
focus and give a F5.6.

Note, it is important to have the chip the correct distance from the rear of the
reducer optics in order to get the best corrected flat field.  This varies with
different reducers. The older reducer is 52.5 mm.  My filter wheel gets me close
to that.  This only becomes a major issue with larger chips.

Lynn

--- In William-Optics@yahoogroups.com, Mark Acker <markacker@...> wrote:
>
> Great info.  Did you use the WO FR?  Was this the II or III?
>
> Thanks Lynn,
> Mark
>
> --- On Sun, 11/15/09, kupainter <no_reply@yahoogroups.com> wrote:
>
> From: kupainter <no_reply@yahoogroups.com>
> Subject: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@yahoogroups.com
> Date: Sunday, November 15, 2009, 9:26 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
>
>
> Hi Mark, I have a older Megrez 80 II ED triplet.  I use Starlight Xpress
Cameras (HX916 and SXVF-H9).  They both are 17 mm from the front of the camera
to the chip.  I could not reach focus with two 2" extension tubes.  These
telescope tubes are cut short so they can be used with a binoviewer.
>
>
>
> I can reach focus with a 0.8x focal reducer.  This shortens the focal length
and allows me to reach focus  with one 2" extension tube.
>
> This also gives a wider field of view at F5.6.
>
>
>
> Lynn
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > I know this has been discussed several times in the past, but wow, I am
having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI
IIIc and in order to reach focus, I have to have the focuser racked almost all
the way out and still need 2-2" extensions.  The only way I can parfocalize an
EP is to go straight into the second extension without the use of a diagonal. 
I am exploring other scope options at the moment, but I won't be making a change
immediately.
>
> > The actual issue here is flexure being introduced by the need for 2
extensions.  Am I missing something here or is this a known thing with the
Megrez line?  Is there a single 4" extension to be had somewhere or is this
some sort of custom job for someone?
>
> > Any insights would be greatly appreciated.
>
> >
>
> > Thank you for your thoughts,
>
> > Mark
>
> >
>

Reply | Forward | Messages in this Topic (19)
#20564 From: "skyclear012" <skyclear012@...>
Date: Wed Nov 18, 2009 4:40 am
Subject: Optically which is better for imaging 		skyclear012
Offline Offline
Send Email Send Email
  
Which telescope is better for imaging between the Megrez 90FD and Megrez 80FD
doublet (TMB apograde lens). Are the TMB lens any better than Megrez 90FD lens?

Reply | Forward | Messages in this Topic (1)
#20565 From: "moxica17" <johanlists@...>
Date: Wed Nov 18, 2009 2:48 pm
Subject: Field size of sky imaged 		moxica17
Offline Offline
Send Email Send Email
  
Good day

I am interested in matching a Canon 40D to a William Optics Zenith Star II 80ED.

I would like to know how much sky will be captured (width and breadth in
degrees) - with and without a WO field flattener?

Thanks

Reply | Forward | Messages in this Topic (2)
#20566 From: Perry Holcomb <hpholcomb@...>
Date: Wed Nov 18, 2009 3:23 pm
Subject: Re: [William Optics] Re: Reaching focus on a Megrez 		hpholcomb
Offline Offline
Send Email Send Email
 
Lynn and all,

The first WO FR/FF, sometimes known as the "I", is designated by the "APO" inscription on the body.  So, it's often known by that.

That was succeeded by the "II", also known as the FLAT2.

That was succeeded by the "III", also known as the FLAT3.

All those were 0.8X reducers.

Then on, ad nauseum...

But the continuing "consumer mystery" here with WO, is what goes with which WO scope? 

Have always found that amusing, especially the way some of these were released touting they were recommended for "X" and "Y" and "Z" WO scopes and then later WO said that no, it wasn't OK for "Z" scope.  That's happened more than once, BTW.

Perry

--- On Tue, 11/17/09, kupainter <no_reply@yahoogroups.com> wrote:

From: kupainter <no_reply@yahoogroups.com>
Subject: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@yahoogroups.com
Date: Tuesday, November 17, 2009, 8:36 PM

 

Mark, it is the older version. The one that WO first came out with. I guess you would call it the I. I have the II, but I use that one on my WO66 so I can get it to come to focus with a SXV guide camera. I think any 0.8x reducer would work for focus. The II and III give a flatter field for larger chips. Some prefer the TeleVue.

I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x Reducer/Corrector with a Astro Tech AT111ED. For the same reason. To bring to focus and give a F5.6.

Note, it is important to have the chip the correct distance from the rear of the reducer optics in order to get the best corrected flat field. This varies with different reducers. The older reducer is 52.5 mm. My filter wheel gets me close to that. This only becomes a major issue with larger chips.

Lynn

--- In William-Optics@ yahoogroups. com, Mark Acker <markacker@. ..> wrote:
>
> Great info.  Did you use the WO FR?  Was this the II or III?
>
> Thanks Lynn,
> Mark
>
> --- On Sun, 11/15/09, kupainter <no_reply@yahoogroup s.com> wrote:
>
> From: kupainter <no_reply@yahoogroup s.com>
> Subject: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@ yahoogroups. com
> Date: Sunday, November 15, 2009, 9:26 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
>
>
> Hi Mark, I have a older Megrez 80 II ED triplet. I use Starlight Xpress Cameras (HX916 and SXVF-H9). They both are 17 mm from the front of the camera to the chip. I could not reach focus with two 2" extension tubes. These telescope tubes are cut short so they can be used with a binoviewer.
>
>
>
> I can reach focus with a 0.8x focal reducer. This shortens the focal length and allows me to reach focus with one 2" extension tube.
>
> This also gives a wider field of view at F5.6.
>
>
>
> Lynn
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
>
> > The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
>
> > Any insights would be greatly appreciated.
>
> >
>
> > Thank you for your thoughts,
>
> > Mark
>
> >
>



Reply | Forward | Messages in this Topic (19)
#20567 From: Delyan Toshev <delyant@...>
Date: Wed Nov 18, 2009 4:46 pm
Subject: Re: [William Optics] Field size of sky imaged 		delyant
Offline Offline
Send Email Send Email
  
Hello,
I propose to you or others interested to view this FOV visualisation
http://www.12dstring.me.uk/fov.php , that I use over a year now and
find one of the best available. I do not know the author of this site,
but he deserves a big THANKS!

Regards,
Delyan Toshev



On Wed, Nov 18, 2009 at 4:48 PM, moxica17 <johanlists@...> wrote:
> Good day
>
> I am interested in matching a Canon 40D to a William Optics Zenith Star II
80ED.
>
> I would like to know how much sky will be captured (width and breadth in
degrees) - with and without a WO field flattener?
>
> Thanks
>

Reply | Forward | Messages in this Topic (2)
#20568 From: Mark Acker <markacker@...>
Date: Wed Nov 18, 2009 9:00 pm
Subject: Re: [William Optics] Re: Reaching focus on a Megrez 		markacker
Offline Offline
Send Email Send Email
 
Thank you Lynn.  I will start looking for a reducer and see how it goes.  Sounds like it is a much better option all the way around since it does more than just increase the distance.

--- On Tue, 11/17/09, kupainter <no_reply@yahoogroups.com> wrote:

From: kupainter <no_reply@yahoogroups.com>
Subject: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@yahoogroups.com
Date: Tuesday, November 17, 2009, 7:36 PM

 

Mark, it is the older version. The one that WO first came out with. I guess you would call it the I. I have the II, but I use that one on my WO66 so I can get it to come to focus with a SXV guide camera. I think any 0.8x reducer would work for focus. The II and III give a flatter field for larger chips. Some prefer the TeleVue.

I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x Reducer/Corrector with a Astro Tech AT111ED. For the same reason. To bring to focus and give a F5.6.

Note, it is important to have the chip the correct distance from the rear of the reducer optics in order to get the best corrected flat field. This varies with different reducers. The older reducer is 52.5 mm. My filter wheel gets me close to that. This only becomes a major issue with larger chips.

Lynn

--- In William-Optics@ yahoogroups. com, Mark Acker <markacker@. ..> wrote:
>
> Great info.  Did you use the WO FR?  Was this the II or III?
>
> Thanks Lynn,
> Mark
>
> --- On Sun, 11/15/09, kupainter <no_reply@yahoogroup s.com> wrote:
>
> From: kupainter <no_reply@yahoogroup s.com>
> Subject: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@ yahoogroups. com
> Date: Sunday, November 15, 2009, 9:26 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
>
>
> Hi Mark, I have a older Megrez 80 II ED triplet. I use Starlight Xpress Cameras (HX916 and SXVF-H9). They both are 17 mm from the front of the camera to the chip. I could not reach focus with two 2" extension tubes. These telescope tubes are cut short so they can be used with a binoviewer.
>
>
>
> I can reach focus with a 0.8x focal reducer. This shortens the focal length and allows me to reach focus with one 2" extension tube.
>
> This also gives a wider field of view at F5.6.
>
>
>
> Lynn
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
>
> > The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
>
> > Any insights would be greatly appreciated.
>
> >
>
> > Thank you for your thoughts,
>
> > Mark
>
> >
>


Reply | Forward | Messages in this Topic (19)
#20569 From: Mark Acker <markacker@...>
Date: Fri Nov 20, 2009 6:56 pm
Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question 		markacker
Offline Offline
Send Email Send Email
 
So, before I place an order for one, can I be reasonably certain that the FLAT2 will work on an 80mm Megrez II?
These things seem to be ridiculously hard to find, but I may have a line on one.

Thanks for everyone's patience with this,
Mark

--- On Wed, 11/18/09, Perry Holcomb <hpholcomb@...> wrote:

From: Perry Holcomb <hpholcomb@...>
Subject: Re: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@yahoogroups.com
Date: Wednesday, November 18, 2009, 9:23 AM

 

Lynn and all,

The first WO FR/FF, sometimes known as the "I", is designated by the "APO" inscription on the body.  So, it's often known by that.

That was succeeded by the "II", also known as the FLAT2.

That was succeeded by the "III", also known as the FLAT3.

All those were 0.8X reducers.

Then on, ad nauseum...

But the continuing "consumer mystery" here with WO, is what goes with which WO scope? 

Have always found that amusing, especially the way some of these were released touting they were recommended for "X" and "Y" and "Z" WO scopes and then later WO said that no, it wasn't OK for "Z" scope.  That's happened more than once, BTW.

Perry

--- On Tue, 11/17/09, kupainter <no_reply@yahoogroup s.com> wrote:

From: kupainter <no_reply@yahoogroup s.com>
Subject: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@ yahoogroups. com
Date: Tuesday, November 17, 2009, 8:36 PM

 

Mark, it is the older version. The one that WO first came out with. I guess you would call it the I. I have the II, but I use that one on my WO66 so I can get it to come to focus with a SXV guide camera. I think any 0.8x reducer would work for focus. The II and III give a flatter field for larger chips. Some prefer the TeleVue.

I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x Reducer/Corrector with a Astro Tech AT111ED. For the same reason. To bring to focus and give a F5.6.

Note, it is important to have the chip the correct distance from the rear of the reducer optics in order to get the best corrected flat field. This varies with different reducers. The older reducer is 52.5 mm. My filter wheel gets me close to that. This only becomes a major issue with larger chips.

Lynn

--- In William-Optics@ yahoogroups. com, Mark Acker <markacker@. ..> wrote:
>
> Great info.  Did you use the WO FR?  Was this the II or III?
>
> Thanks Lynn,
> Mark
>
> --- On Sun, 11/15/09, kupainter <no_reply@yahoogroup s.com> wrote:
>
> From: kupainter <no_reply@yahoogroup s.com>
> Subject: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@ yahoogroups. com
> Date: Sunday, November 15, 2009, 9:26 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
>
>
> Hi Mark, I have a older Megrez 80 II ED triplet. I use Starlight Xpress Cameras (HX916 and SXVF-H9). They both are 17 mm from the front of the camera to the chip. I could not reach focus with two 2" extension tubes. These telescope tubes are cut short so they can be used with a binoviewer.
>
>
>
> I can reach focus with a 0.8x focal reducer. This shortens the focal length and allows me to reach focus with one 2" extension tube.
>
> This also gives a wider field of view at F5.6.
>
>
>
> Lynn
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
>
> > The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
>
> > Any insights would be greatly appreciated.
>
> >
>
> > Thank you for your thoughts,
>
> > Mark
>
> >
>



Reply | Forward | Messages in this Topic (19)
#20570 From: Perry Holcomb <hpholcomb@...>
Date: Sat Nov 21, 2009 3:10 am
Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question 		hpholcomb
Offline Offline
Send Email Send Email
 
Hey Mark,

No, you can't be certain it'll work.

WO does not recommend the FLAT2 for the M80.  It recommends the FLAT3.  See:

http://www.williamoptics.com/accessories/flattener3_features.php

However, that does not mean you can't successfully use a non-WO FR/FF with the M80.

Televue makes a respected FR/FF, the TRF-2008.  For that see:

http://www.televue.com/engine/page.asp?ID=169

The final sentence in the description of the TV FR/FF is,  "Also it can be used with any 400-600mm refractor."

Isn't the M80 II triplet somewhere in the high 500mms FL??

Anyway, that's only given as food for thought.  I'm not recommending either because I don't have an M80II.  I'm only mentioning them for possible further research you need to do before buying.

And after that, if you still are somewhat unsure but have made a choice, buy one used!!!!!!!!

Regards, and good luck,

Perry

--- On Fri, 11/20/09, Mark Acker <markacker@...> wrote:

From: Mark Acker <markacker@...>
Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
To: William-Optics@yahoogroups.com
Date: Friday, November 20, 2009, 1:56 PM

 

So, before I place an order for one, can I be reasonably certain that the FLAT2 will work on an 80mm Megrez II?
These things seem to be ridiculously hard to find, but I may have a line on one.

Thanks for everyone's patience with this,
Mark

--- On Wed, 11/18/09, Perry Holcomb <hpholcomb@yahoo. com> wrote:

From: Perry Holcomb <hpholcomb@yahoo. com>
Subject: Re: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@ yahoogroups. com
Date: Wednesday, November 18, 2009, 9:23 AM

 

Lynn and all,

The first WO FR/FF, sometimes known as the "I", is designated by the "APO" inscription on the body.  So, it's often known by that.

That was succeeded by the "II", also known as the FLAT2.

That was succeeded by the "III", also known as the FLAT3.

All those were 0.8X reducers.

Then on, ad nauseum...

But the continuing "consumer mystery" here with WO, is what goes with which WO scope? 

Have always found that amusing, especially the way some of these were released touting they were recommended for "X" and "Y" and "Z" WO scopes and then later WO said that no, it wasn't OK for "Z" scope.  That's happened more than once, BTW.

Perry

--- On Tue, 11/17/09, kupainter <no_reply@yahoogroup s.com> wrote:

From: kupainter <no_reply@yahoogroup s.com>
Subject: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@ yahoogroups. com
Date: Tuesday, November 17, 2009, 8:36 PM

 

Mark, it is the older version. The one that WO first came out with. I guess you would call it the I. I have the II, but I use that one on my WO66 so I can get it to come to focus with a SXV guide camera. I think any 0.8x reducer would work for focus. The II and III give a flatter field for larger chips. Some prefer the TeleVue.

I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x Reducer/Corrector with a Astro Tech AT111ED. For the same reason. To bring to focus and give a F5.6.

Note, it is important to have the chip the correct distance from the rear of the reducer optics in order to get the best corrected flat field. This varies with different reducers. The older reducer is 52.5 mm. My filter wheel gets me close to that. This only becomes a major issue with larger chips.

Lynn

--- In William-Optics@ yahoogroups. com, Mark Acker <markacker@. ..> wrote:
>
> Great info.  Did you use the WO FR?  Was this the II or III?
>
> Thanks Lynn,
> Mark
>
> --- On Sun, 11/15/09, kupainter <no_reply@yahoogroup s.com> wrote:
>
> From: kupainter <no_reply@yahoogroup s.com>
> Subject: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@ yahoogroups. com
> Date: Sunday, November 15, 2009, 9:26 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
>
>
> Hi Mark, I have a older Megrez 80 II ED triplet. I use Starlight Xpress Cameras (HX916 and SXVF-H9). They both are 17 mm from the front of the camera to the chip. I could not reach focus with two 2" extension tubes. These telescope tubes are cut short so they can be used with a binoviewer.
>
>
>
> I can reach focus with a 0.8x focal reducer. This shortens the focal length and allows me to reach focus with one 2" extension tube.
>
> This also gives a wider field of view at F5.6.
>
>
>
> Lynn
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
>
> > The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
>
> > Any insights would be greatly appreciated.
>
> >
>
> > Thank you for your thoughts,
>
> > Mark
>
> >
>




Reply | Forward | Messages in this Topic (19)
#20571 From: Mark Acker <markacker@...>
Date: Sat Nov 21, 2009 6:31 am
Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question 		markacker
Offline Offline
Send Email Send Email
 
That ambiguity was what actually led to the question.  ;)   I am going to see if I can get a FLAT3 as that one does seem to have a higher probability of success.
Thanks Perry.

--- On Fri, 11/20/09, Perry Holcomb <hpholcomb@...> wrote:

From: Perry Holcomb <hpholcomb@...>
Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
To: William-Optics@yahoogroups.com
Date: Friday, November 20, 2009, 9:10 PM

 

Hey Mark,

No, you can't be certain it'll work.

WO does not recommend the FLAT2 for the M80.  It recommends the FLAT3.  See:

http://www.williamo ptics.com/ accessories/ flattener3_ features. php

However, that does not mean you can't successfully use a non-WO FR/FF with the M80.

Televue makes a respected FR/FF, the TRF-2008.  For that see:

http://www.televue. com/engine/ page.asp? ID=169

The final sentence in the description of the TV FR/FF is,  "Also it can be used with any 400-600mm refractor."

Isn't the M80 II triplet somewhere in the high 500mms FL??

Anyway, that's only given as food for thought.  I'm not recommending either because I don't have an M80II.  I'm only mentioning them for possible further research you need to do before buying.

And after that, if you still are somewhat unsure but have made a choice, buy one used!!!!!!!!

Regards, and good luck,

Perry

--- On Fri, 11/20/09, Mark Acker <markacker@yahoo. com> wrote:

From: Mark Acker <markacker@yahoo. com>
Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
To: William-Optics@ yahoogroups. com
Date: Friday, November 20, 2009, 1:56 PM

 

So, before I place an order for one, can I be reasonably certain that the FLAT2 will work on an 80mm Megrez II?
These things seem to be ridiculously hard to find, but I may have a line on one.

Thanks for everyone's patience with this,
Mark

--- On Wed, 11/18/09, Perry Holcomb <hpholcomb@yahoo. com> wrote:

From: Perry Holcomb <hpholcomb@yahoo. com>
Subject: Re: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@ yahoogroups. com
Date: Wednesday, November 18, 2009, 9:23 AM

 

Lynn and all,

The first WO FR/FF, sometimes known as the "I", is designated by the "APO" inscription on the body.  So, it's often known by that.

That was succeeded by the "II", also known as the FLAT2.

That was succeeded by the "III", also known as the FLAT3.

All those were 0.8X reducers.

Then on, ad nauseum...

But the continuing "consumer mystery" here with WO, is what goes with which WO scope? 

Have always found that amusing, especially the way some of these were released touting they were recommended for "X" and "Y" and "Z" WO scopes and then later WO said that no, it wasn't OK for "Z" scope.  That's happened more than once, BTW.

Perry

--- On Tue, 11/17/09, kupainter <no_reply@yahoogroup s.com> wrote:

From: kupainter <no_reply@yahoogroup s.com>
Subject: [William Optics] Re: Reaching focus on a Megrez
To: William-Optics@ yahoogroups. com
Date: Tuesday, November 17, 2009, 8:36 PM

 

Mark, it is the older version. The one that WO first came out with. I guess you would call it the I. I have the II, but I use that one on my WO66 so I can get it to come to focus with a SXV guide camera. I think any 0.8x reducer would work for focus. The II and III give a flatter field for larger chips. Some prefer the TeleVue.

I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x Reducer/Corrector with a Astro Tech AT111ED. For the same reason. To bring to focus and give a F5.6.

Note, it is important to have the chip the correct distance from the rear of the reducer optics in order to get the best corrected flat field. This varies with different reducers. The older reducer is 52.5 mm. My filter wheel gets me close to that. This only becomes a major issue with larger chips.

Lynn

--- In William-Optics@ yahoogroups. com, Mark Acker <markacker@. ..> wrote:
>
> Great info.  Did you use the WO FR?  Was this the II or III?
>
> Thanks Lynn,
> Mark
>
> --- On Sun, 11/15/09, kupainter <no_reply@yahoogroup s.com> wrote:
>
> From: kupainter <no_reply@yahoogroup s.com>
> Subject: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@ yahoogroups. com
> Date: Sunday, November 15, 2009, 9:26 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
>
>
> Hi Mark, I have a older Megrez 80 II ED triplet. I use Starlight Xpress Cameras (HX916 and SXVF-H9). They both are 17 mm from the front of the camera to the chip. I could not reach focus with two 2" extension tubes. These telescope tubes are cut short so they can be used with a binoviewer.
>
>
>
> I can reach focus with a 0.8x focal reducer. This shortens the focal length and allows me to reach focus with one 2" extension tube.
>
> This also gives a wider field of view at F5.6.
>
>
>
> Lynn
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
>
> > The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
>
> > Any insights would be greatly appreciated.
>
> >
>
> > Thank you for your thoughts,
>
> > Mark
>
> >
>




Reply | Forward | Messages in this Topic (19)
#20572 From: "notgnirramot" <notgnirra@...>
Date: Sat Nov 21, 2009 1:56 pm
Subject: [William Optics] Re: Reaching focus on a Megrez--last question 		notgnirramot
Offline Offline
Send Email Send Email
  
Hi Mark,

Let me add a little to this discussion.

I have the Megrez Fluorite Doublet f/6.9 with a focal length of 555mm.  I image
with a Canon Rebel XT DSLR and get very good results with the W/O FLAT2.

I also have a FluoroStar 110mm f/7.0 with a focal length of 770.  I purchased a
W/O FALT3 for it based on the W/O recommendations on the web site.  It actually
worsens the coma!  I have used the FLAT2 with the FluoroStar with much better
results, not perfect but better than with no flatener.  I will try the FLAT4
based on correspondence with W/O.

I have not tried the FLAT3 on my Megrez.

I believe your scope is the Megrez II ED Triplet which is f/7 with a focal
length of 560mm.  Pretty close numbers to my Megrez.

The FLAT2 has a good reputation in the DSLR imaging world with many Orion 80ED,
fl 600, users showing great success with that reducer flattener.  It seems to be
a very good product for scopes in the size and focal length range of your scope.

Plus if you were to get one and decide to try something else there would be a
good market to resell it.  I've not seen a single good reveiw of the FLAT3 and
it might be harder to resell.

Hope that helps.

Tom

--- In William-Optics@yahoogroups.com, Mark Acker <markacker@...> wrote:
>
> That ambiguity was what actually led to the question.  ;)   I am going to
see if I can get a FLAT3 as that one does seem to have a higher probability of
success.
> Thanks Perry.
>
> --- On Fri, 11/20/09, Perry Holcomb <hpholcomb@...> wrote:
>
> From: Perry Holcomb <hpholcomb@...>
> Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
> To: William-Optics@yahoogroups.com
> Date: Friday, November 20, 2009, 9:10 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
>       Hey Mark,
>
> No, you can't be certain it'll work.
>
> WO does not recommend the FLAT2 for the M80.  It recommends the FLAT3.  See:
>
> http://www.williamo ptics.com/ accessories/ flattener3_ features. php
>
> However, that does not mean you can't successfully use a non-WO FR/FF with the
M80.
>
> Televue makes a respected FR/FF, the TRF-2008.  For that see:
>
> http://www.televue. com/engine/ page.asp? ID=169
>
> The final sentence in the description of the TV FR/FF is,  "Also it can be
>   used with any 400-600mm refractor."
>
> Isn't the M80 II triplet somewhere in the high 500mms FL??
>
> Anyway, that's only given as food for thought.  I'm not recommending either
because I don't have an M80II.  I'm only mentioning them for possible further
research you need to do before buying.
>
> And after that, if you still are somewhat unsure but have made a choice, buy
one used!!!!!!!!
>
> Regards, and good luck,
>
> Perry
>
> --- On Fri, 11/20/09, Mark Acker <markacker@yahoo. com> wrote:
>
> From: Mark Acker <markacker@yahoo. com>
> Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
> To: William-Optics@ yahoogroups. com
> Date: Friday, November 20, 2009, 1:56 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>       So, before I place an order for one, can I be reasonably certain that
the FLAT2 will work on an 80mm Megrez II?
> These things seem to be ridiculously hard to find, but I may have a line on
one.
>
> Thanks for everyone's patience with this,
> Mark
>
> --- On Wed, 11/18/09, Perry Holcomb <hpholcomb@yahoo. com> wrote:
>
> From: Perry Holcomb <hpholcomb@yahoo. com>
> Subject: Re: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@ yahoogroups. com
> Date: Wednesday, November 18, 2009, 9:23 AM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>       Lynn and all,
>
> The first WO FR/FF, sometimes known as the "I", is designated by the "APO"
inscription on the body.  So, it's often known by that.
>
> That was succeeded by the "II", also known as the FLAT2.
>
> That was succeeded by the "III", also known as the FLAT3.
>
> All those were 0.8X reducers.
>
> Then on, ad nauseum...
>
> But the continuing "consumer mystery" here with WO, is what goes with which WO
scope? 
>
> Have always found that amusing, especially the way some of these were released
touting they were recommended for "X" and "Y" and "Z" WO scopes and then later
WO said that no, it wasn't OK for "Z" scope. 
>  That's happened more than once, BTW.
>
> Perry
>
> --- On Tue, 11/17/09, kupainter <no_reply@yahoogroup s.com> wrote:
>
> From: kupainter <no_reply@yahoogroup s.com>
> Subject: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@ yahoogroups. com
> Date: Tuesday, November 17, 2009, 8:36 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>       Mark, it is the older version. The one that WO first came out with. I
guess you would call it the I. I have the II, but I use that one on my WO66 so I
can get it to come to focus with a SXV guide camera. I think any 0.8x reducer
would work for focus.  The II and III give a flatter field for larger chips.
Some prefer the TeleVue.
>
>
>
> I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x
Reducer/Corrector with a Astro Tech AT111ED.  For the same reason. To bring to
focus and give a F5.6.
>
>
>
> Note, it is important to have the chip the correct distance from the rear of
the reducer optics in order to get the best corrected flat field.  This varies
with different reducers. The older reducer is 52.5 mm.  My filter wheel gets me
close to that.  This only becomes a major issue with larger chips.
>
>
>
> Lynn
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > Great info.  Did you use the WO FR?  Was this the II or III?
>
> >
>
> > Thanks Lynn,
>
> > Mark
>
> >
>
> > --- On Sun, 11/15/09, kupainter <no_reply@yahoogroup s.com> wrote:
>
> >
>
> > From: kupainter <no_reply@yahoogroup s.com>
>
> > Subject: [William Optics] Re: Reaching focus on a Megrez
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Sunday, November 15, 2009, 9:26 PM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > Hi Mark, I have a older Megrez 80 II ED triplet.  I use Starlight Xpress
Cameras (HX916 and SXVF-H9).  They both are 17 mm from the front of the camera
to the chip.  I could not reach focus with two 2" extension tubes.  These
telescope tubes are cut short so they can be used with a binoviewer.
>
> >
>
> >
>
> >
>
> > I can reach focus with a 0.8x focal reducer.  This shortens the focal length
and allows me to reach focus  with one 2" extension tube.
>
> >
>
> > This also gives a wider field of view at F5.6.
>
> >
>
> >
>
> >
>
> > Lynn
>
> >
>
> >
>
> >
>
> > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > >
>
> >
>
> > > I know this has been discussed several times in the past, but wow, I am
having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade
DSI IIIc and in order to reach focus, I have to have the focuser racked almost
all the way out and still need 2-2" extensions.  The only way I can
parfocalize an EP is to go straight into the second extension without the use of
a diagonal.  I am exploring other scope options at the moment, but I won't be
making a change immediately.
>
> >
>
> > > The actual issue here is flexure being introduced by the need for 2
extensions.  Am I missing something here or is this a known thing with the
Megrez line?  Is there a single 4" extension to be had somewhere or is this
some sort of custom job for someone?
>
> >
>
> > > Any insights would be greatly appreciated.
>
> >
>
> > >
>
> >
>
> > > Thank you for your thoughts,
>
> >
>
> > > Mark
>
> >
>
> > >
>
> >
>

Reply | Forward | Messages in this Topic (19)
#20573 From: Mark Acker <markacker@...>
Date: Sat Nov 21, 2009 7:13 pm
Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question 		markacker
Offline Offline
Send Email Send Email
 
Thanks for your thoughts Tom.  You are correct about the Megrez's numbers.  I was about to give in and get the FLAT3 just because they are easier, if more expensive, to buy.  I think I am going to just hold out until I can get the FLAT2 instead.
Just to reiterate, the initial purpose of this discussion was less to improve image quality and more to shorten the train back to the camera to eliminate some flexure.  This seems to have been largely accomplished by just making sure the focuser tube and rotator screws are tightened fully after getting focused.  I felt like a dufus when that suggestion was initially pointed out and it turned out to work beautifully.  Also, by changing the mount configuration around and eliminating a dual mounting plate and 80mm guide scope, the balance issue was resolved as well.

Thanks all,
Mark

--- On Sat, 11/21/09, notgnirramot <notgnirra@...> wrote:

From: notgnirramot <notgnirra@...>
Subject: [William Optics] Re: Reaching focus on a Megrez--last question
To: William-Optics@yahoogroups.com
Date: Saturday, November 21, 2009, 7:56 AM

 

Hi Mark,

Let me add a little to this discussion.

I have the Megrez Fluorite Doublet f/6.9 with a focal length of 555mm. I image with a Canon Rebel XT DSLR and get very good results with the W/O FLAT2.

I also have a FluoroStar 110mm f/7.0 with a focal length of 770. I purchased a W/O FALT3 for it based on the W/O recommendations on the web site. It actually worsens the coma! I have used the FLAT2 with the FluoroStar with much better results, not perfect but better than with no flatener. I will try the FLAT4 based on correspondence with W/O.

I have not tried the FLAT3 on my Megrez.

I believe your scope is the Megrez II ED Triplet which is f/7 with a focal length of 560mm. Pretty close numbers to my Megrez.

The FLAT2 has a good reputation in the DSLR imaging world with many Orion 80ED, fl 600, users showing great success with that reducer flattener. It seems to be a very good product for scopes in the size and focal length range of your scope.

Plus if you were to get one and decide to try something else there would be a good market to resell it. I've not seen a single good reveiw of the FLAT3 and it might be harder to resell.

Hope that helps.

Tom

--- In William-Optics@ yahoogroups. com, Mark Acker <markacker@. ..> wrote:
>
> That ambiguity was what actually led to the question.  ;) Â  I am going to see if I can get a FLAT3 as that one does seem to have a higher probability of success.
> Thanks Perry.
>
> --- On Fri, 11/20/09, Perry Holcomb <hpholcomb@. ..> wrote:
>
> From: Perry Holcomb <hpholcomb@. ..>
> Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
> To: William-Optics@ yahoogroups. com
> Date: Friday, November 20, 2009, 9:10 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
> Hey Mark,
>
> No, you can't be certain it'll work.
>
> WO does not recommend the FLAT2 for the M80.  It recommends the FLAT3.  See:
>
> http://www.williamo ptics.com/ accessories/ flattener3_ features. php
>
> However, that does not mean you can't successfully use a non-WO FR/FF with the M80.
>
> Televue makes a respected FR/FF, the TRF-2008.  For that see:
>
> http://www.televue. com/engine/ page.asp? ID=169
>
> The final sentence in the description of the TV FR/FF is,  "Also it can be
> used with any 400-600mm refractor."
>
> Isn't the M80 II triplet somewhere in the high 500mms FL??
>
> Anyway, that's only given as food for thought.  I'm not recommending either because I don't have an M80II.  I'm only mentioning them for possible further research you need to do before buying.
>
> And after that, if you still are somewhat unsure but have made a choice, buy one used!!!!!!!!
>
> Regards, and good luck,
>
> Perry
>
> --- On Fri, 11/20/09, Mark Acker <markacker@yahoo. com> wrote:
>
> From: Mark Acker <markacker@yahoo. com>
> Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
> To: William-Optics@ yahoogroups. com
> Date: Friday, November 20, 2009, 1:56 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
> So, before I place an order for one, can I be reasonably certain that the FLAT2 will work on an 80mm Megrez II?
> These things seem to be ridiculously hard to find, but I may have a line on one.
>
> Thanks for everyone's patience with this,
> Mark
>
> --- On Wed, 11/18/09, Perry Holcomb <hpholcomb@yahoo. com> wrote:
>
> From: Perry Holcomb <hpholcomb@yahoo. com>
> Subject: Re: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@ yahoogroups. com
> Date: Wednesday, November 18, 2009, 9:23 AM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
> Lynn and all,
>
> The first WO FR/FF, sometimes known as the "I", is designated by the "APO" inscription on the body.  So, it's often known by that.
>
> That was succeeded by the "II", also known as the FLAT2.
>
> That was succeeded by the "III", also known as the FLAT3.
>
> All those were 0.8X reducers.
>
> Then on, ad nauseum...
>
> But the continuing "consumer mystery" here with WO, is what goes with which WO scope? 
>
> Have always found that amusing, especially the way some of these were released touting they were recommended for "X" and "Y" and "Z" WO scopes and then later WO said that no, it wasn't OK for "Z" scope. 
> That's happened more than once, BTW.
>
> Perry
>
> --- On Tue, 11/17/09, kupainter <no_reply@yahoogrou p s.com> wrote:
>
> From: kupainter <no_reply@yahoogrou p s.com>
> Subject: [William Optics] Re: Reaching focus on a Megrez
> To: William-Optics@ yahoogroups. com
> Date: Tuesday, November 17, 2009, 8:36 PM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
> Mark, it is the older version. The one that WO first came out with. I guess you would call it the I. I have the II, but I use that one on my WO66 so I can get it to come to focus with a SXV guide camera. I think any 0.8x reducer would work for focus. The II and III give a flatter field for larger chips. Some prefer the TeleVue.
>
>
>
> I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x Reducer/Corrector with a Astro Tech AT111ED. For the same reason. To bring to focus and give a F5.6.
>
>
>
> Note, it is important to have the chip the correct distance from the rear of the reducer optics in order to get the best corrected flat field. This varies with different reducers. The older reducer is 52.5 mm. My filter wheel gets me close to that. This only becomes a major issue with larger chips.
>
>
>
> Lynn
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > Great info.  Did you use the WO FR?  Was this the II or III?
>
> >
>
> > Thanks Lynn,
>
> > Mark
>
> >
>
> > --- On Sun, 11/15/09, kupainter <no_reply@yahoogrou p s.com> wrote:
>
> >
>
> > From: kupainter <no_reply@yahoogrou p s.com>
>
> > Subject: [William Optics] Re: Reaching focus on a Megrez
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Sunday, November 15, 2009, 9:26 PM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > Hi Mark, I have a older Megrez 80 II ED triplet. I use Starlight Xpress Cameras (HX916 and SXVF-H9). They both are 17 mm from the front of the camera to the chip. I could not reach focus with two 2" extension tubes. These telescope tubes are cut short so they can be used with a binoviewer.
>
> >
>
> >
>
> >
>
> > I can reach focus with a 0.8x focal reducer. This shortens the focal length and allows me to reach focus with one 2" extension tube.
>
> >
>
> > This also gives a wider field of view at F5.6.
>
> >
>
> >
>
> >
>
> > Lynn
>
> >
>
> >
>
> >
>
> > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > >
>
> >
>
> > > I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
>
> >
>
> > > The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
>
> >
>
> > > Any insights would be greatly appreciated.
>
> >
>
> > >
>
> >
>
> > > Thank you for your thoughts,
>
> >
>
> > > Mark
>
> >
>
> > >
>
> >
>


Reply | Forward | Messages in this Topic (19)
#20574 From: "notgnirramot" <notgnirra@...>
Date: Sun Nov 22, 2009 2:09 am
Subject: [William Optics] Re: Reaching focus on a Megrez--last question 		notgnirramot
Offline Offline
Send Email Send Email
  
Mark,

Glad I could help.

For focusing, have you tried a Bahtinov Mask?  I swithed to one from
http://www.focus-mask.com/ and won't leave home without it!  I was using
software that calculated several focus numbers to help maximize the focus.  The
mask is much quicker, more consistent, and results in a better focus.

If you are handy and have the time this site also has templates to download so
you can cut your own.  The templates are free!

Tom

--- In William-Optics@yahoogroups.com, Mark Acker <markacker@...> wrote:
>
> Thanks for your thoughts Tom.  You are correct about the Megrez's numbers. 
I was about to give in and get the FLAT3 just because they are easier, if more
expensive, to buy.  I think I am going to just hold out until I can get the
FLAT2 instead.
> Just to reiterate, the initial purpose of this discussion was less to improve
image quality and more to shorten the train back to the camera to eliminate some
flexure.  This seems to have been largely accomplished by just making sure the
focuser tube and rotator screws are tightened fully after getting focused.  I
felt like a dufus when that suggestion was initially pointed out and it turned
out to work beautifully.  Also, by changing the mount configuration around and
eliminating a dual mounting plate and 80mm guide scope, the balance issue was
resolved as well.
>
> Thanks all,
> Mark
>
> --- On Sat, 11/21/09, notgnirramot <notgnirra@...> wrote:
>
> From: notgnirramot <notgnirra@...>
> Subject: [William Optics] Re: Reaching focus on a Megrez--last question
> To: William-Optics@yahoogroups.com
> Date: Saturday, November 21, 2009, 7:56 AM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
>       Hi Mark,
>
>
>
> Let me add a little to this discussion.
>
>
>
> I have the Megrez Fluorite Doublet f/6.9 with a focal length of 555mm.  I
image with a Canon Rebel XT DSLR and get very good results with the W/O FLAT2.
>
>
>
> I also have a FluoroStar 110mm f/7.0 with a focal length of 770.  I purchased
a W/O FALT3 for it based on the W/O recommendations on the web site.  It
actually worsens the coma!  I have used the FLAT2 with the FluoroStar with much
better results, not perfect but better than with no flatener.  I will try the
FLAT4 based on correspondence with W/O.
>
>
>
> I have not tried the FLAT3 on my Megrez.
>
>
>
> I believe your scope is the Megrez II ED Triplet which is f/7 with a focal
length of 560mm.  Pretty close numbers to my Megrez.
>
>
>
> The FLAT2 has a good reputation in the DSLR imaging world with many Orion
80ED, fl 600, users showing great success with that reducer flattener.  It seems
to be a very good product for scopes in the size and focal length range of your
scope.
>
>
>
> Plus if you were to get one and decide to try something else there would be a
good market to resell it.  I've not seen a single good reveiw of the FLAT3 and
it might be harder to resell.
>
>
>
> Hope that helps.
>
>
>
> Tom
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > That ambiguity was what actually led to the question.  ;)   I am
going to see if I can get a FLAT3 as that one does seem to have a higher
probability of success.
>
> > Thanks Perry.
>
> >
>
> > --- On Fri, 11/20/09, Perry Holcomb <hpholcomb@ ..> wrote:
>
> >
>
> > From: Perry Holcomb <hpholcomb@ ..>
>
> > Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Friday, November 20, 2009, 9:10 PM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >       Hey Mark,
>
> >
>
> > No, you can't be certain it'll work.
>
> >
>
> > WO does not recommend the FLAT2 for the M80.  It recommends the
FLAT3.  See:
>
> >
>
> > http://www.williamo ptics.com/ accessories/ flattener3_ features. php
>
> >
>
> > However, that does not mean you can't successfully use a non-WO FR/FF with
the M80.
>
> >
>
> > Televue makes a respected FR/FF, the TRF-2008.  For that see:
>
> >
>
> > http://www.televue. com/engine/ page.asp? ID=169
>
> >
>
> > The final sentence in the description of the TV FR/FF is,  "Also it can
be
>
> >   used with any 400-600mm refractor."
>
> >
>
> > Isn't the M80 II triplet somewhere in the high 500mms FL??
>
> >
>
> > Anyway, that's only given as food for thought.  I'm not recommending
either because I don't have an M80II.  I'm only mentioning them for possible
further research you need to do before buying.
>
> >
>
> > And after that, if you still are somewhat unsure but have made a choice, buy
one used!!!!!!!!
>
> >
>
> > Regards, and good luck,
>
> >
>
> > Perry
>
> >
>
> > --- On Fri, 11/20/09, Mark Acker <markacker@yahoo. com> wrote:
>
> >
>
> > From: Mark Acker <markacker@yahoo. com>
>
> > Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Friday, November 20, 2009, 1:56 PM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >       So, before I place an order for one, can I be reasonably certain that
the FLAT2 will work on an 80mm Megrez II?
>
> > These things seem to be ridiculously hard to find, but I may have a line on
one.
>
> >
>
> > Thanks for everyone's patience with this,
>
> > Mark
>
> >
>
> > --- On Wed, 11/18/09, Perry Holcomb <hpholcomb@yahoo. com> wrote:
>
> >
>
> > From: Perry Holcomb <hpholcomb@yahoo. com>
>
> > Subject: Re: [William Optics] Re: Reaching focus on a Megrez
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Wednesday, November 18, 2009, 9:23 AM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >       Lynn and all,
>
> >
>
> > The first WO FR/FF, sometimes known as the "I", is designated by the "APO"
inscription on the body.  So, it's often known by that.
>
> >
>
> > That was succeeded by the "II", also known as the FLAT2.
>
> >
>
> > That was succeeded by the "III", also known as the FLAT3.
>
> >
>
> > All those were 0.8X reducers.
>
> >
>
> > Then on, ad nauseum...
>
> >
>
> > But the continuing "consumer mystery" here with WO, is what goes with which
WO scope? 
>
> >
>
> > Have always found that amusing, especially the way some of these were
released touting they were recommended for "X" and "Y" and "Z" WO scopes and
then later WO said that no, it wasn't OK for "Z" scope. 
>
> >  That's happened more than once, BTW.
>
> >
>
> > Perry
>
> >
>
> > --- On Tue, 11/17/09, kupainter <no_reply@yahoogrou p s.com> wrote:
>
> >
>
> > From: kupainter <no_reply@yahoogrou p s.com>
>
> > Subject: [William Optics] Re: Reaching focus on a Megrez
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Tuesday, November 17, 2009, 8:36 PM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >       Mark, it is the older version. The one that WO first came out with. I
guess you would call it the I. I have the II, but I use that one on my WO66 so I
can get it to come to focus with a SXV guide camera. I think any 0.8x reducer
would work for focus.  The II and III give a flatter field for larger chips.
Some prefer the TeleVue.
>
> >
>
> >
>
> >
>
> > I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x
Reducer/Corrector with a Astro Tech AT111ED.  For the same reason. To bring to
focus and give a F5.6.
>
> >
>
> >
>
> >
>
> > Note, it is important to have the chip the correct distance from the rear of
the reducer optics in order to get the best corrected flat field.  This varies
with different reducers. The older reducer is 52.5 mm.  My filter wheel gets me
close to that.  This only becomes a major issue with larger chips.
>
> >
>
> >
>
> >
>
> > Lynn
>
> >
>
> >
>
> >
>
> > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > >
>
> >
>
> > > Great info.  Did you use the WO FR?  Was this the II or
III?
>
> >
>
> > >
>
> >
>
> > > Thanks Lynn,
>
> >
>
> > > Mark
>
> >
>
> > >
>
> >
>
> > > --- On Sun, 11/15/09, kupainter <no_reply@yahoogrou p s.com> wrote:
>
> >
>
> > >
>
> >
>
> > > From: kupainter <no_reply@yahoogrou p s.com>
>
> >
>
> > > Subject: [William Optics] Re: Reaching focus on a Megrez
>
> >
>
> > > To: William-Optics@ yahoogroups. com
>
> >
>
> > > Date: Sunday, November 15, 2009, 9:26 PM
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >  
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > Hi Mark, I have a older Megrez 80 II ED triplet.  I use Starlight Xpress
Cameras (HX916 and SXVF-H9).  They both are 17 mm from the front of the camera
to the chip.  I could not reach focus with two 2" extension tubes.  These
telescope tubes are cut short so they can be used with a binoviewer.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > I can reach focus with a 0.8x focal reducer.  This shortens the focal
length and allows me to reach focus  with one 2" extension tube.
>
> >
>
> > >
>
> >
>
> > > This also gives a wider field of view at F5.6.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > Lynn
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > I know this has been discussed several times in the past, but wow, I am
having a heckuva time imaging with a Megrez II 80mm.  The camera is a
Meade DSI IIIc and in order to reach focus, I have to have the focuser racked
almost all the way out and still need 2-2" extensions.  The only way I
can parfocalize an EP is to go straight into the second extension without the
use of a diagonal.  I am exploring other scope options at the moment,
but I won't be making a change immediately.
>
> >
>
> > >
>
> >
>
> > > > The actual issue here is flexure being introduced by the need for 2
extensions.  Am I missing something here or is this a known thing with
the Megrez line?  Is there a single 4" extension to be had somewhere or
is this some sort of custom job for someone?
>
> >
>
> > >
>
> >
>
> > > > Any insights would be greatly appreciated.
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > Thank you for your thoughts,
>
> >
>
> > >
>
> >
>
> > > > Mark
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>

Reply | Forward | Messages in this Topic (19)
#20575 From: Mark Acker <markacker@...>
Date: Sun Nov 22, 2009 2:26 am
Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question 		markacker
Offline Offline
Send Email Send Email
 
I do have one actually.  You are right, it is a useful tool.  I wussed out and just bought one. ;)

--- On Sat, 11/21/09, notgnirramot <notgnirra@...> wrote:

From: notgnirramot <notgnirra@...>
Subject: [William Optics] Re: Reaching focus on a Megrez--last question
To: William-Optics@yahoogroups.com
Date: Saturday, November 21, 2009, 8:09 PM

 

Mark,

Glad I could help.

For focusing, have you tried a Bahtinov Mask? I swithed to one from http://www.focus- mask.com/ and won't leave home without it! I was using software that calculated several focus numbers to help maximize the focus. The mask is much quicker, more consistent, and results in a better focus.

If you are handy and have the time this site also has templates to download so you can cut your own. The templates are free!

Tom

--- In William-Optics@ yahoogroups. com, Mark Acker <markacker@. ..> wrote:
>
> Thanks for your thoughts Tom.  You are correct about the Megrez's numbers.  I was about to give in and get the FLAT3 just because they are easier, if more expensive, to buy.  I think I am going to just hold out until I can get the FLAT2 instead.
> Just to reiterate, the initial purpose of this discussion was less to improve image quality and more to shorten the train back to the camera to eliminate some flexure.  This seems to have been largely accomplished by just making sure the focuser tube and rotator screws are tightened fully after getting focused.  I felt like a dufus when that suggestion was initially pointed out and it turned out to work beautifully.  Also, by changing the mount configuration around and eliminating a dual mounting plate and 80mm guide scope, the balance issue was resolved as well.
>
> Thanks all,
> Mark
>
> --- On Sat, 11/21/09, notgnirramot <notgnirra@. ..> wrote:
>
> From: notgnirramot <notgnirra@. ..>
> Subject: [William Optics] Re: Reaching focus on a Megrez--last question
> To: William-Optics@ yahoogroups. com
> Date: Saturday, November 21, 2009, 7:56 AM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
> Hi Mark,
>
>
>
> Let me add a little to this discussion.
>
>
>
> I have the Megrez Fluorite Doublet f/6.9 with a focal length of 555mm. I image with a Canon Rebel XT DSLR and get very good results with the W/O FLAT2.
>
>
>
> I also have a FluoroStar 110mm f/7.0 with a focal length of 770. I purchased a W/O FALT3 for it based on the W/O recommendations on the web site. It actually worsens the coma! I have used the FLAT2 with the FluoroStar with much better results, not perfect but better than with no flatener. I will try the FLAT4 based on correspondence with W/O.
>
>
>
> I have not tried the FLAT3 on my Megrez.
>
>
>
> I believe your scope is the Megrez II ED Triplet which is f/7 with a focal length of 560mm. Pretty close numbers to my Megrez.
>
>
>
> The FLAT2 has a good reputation in the DSLR imaging world with many Orion 80ED, fl 600, users showing great success with that reducer flattener. It seems to be a very good product for scopes in the size and focal length range of your scope.
>
>
>
> Plus if you were to get one and decide to try something else there would be a good market to resell it. I've not seen a single good reveiw of the FLAT3 and it might be harder to resell.
>
>
>
> Hope that helps.
>
>
>
> Tom
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > That ambiguity was what actually led to the question.  ;) Â  I am going to see if I can get a FLAT3 as that one does seem to have a higher probability of success.
>
> > Thanks Perry.
>
> >
>
> > --- On Fri, 11/20/09, Perry Holcomb <hpholcomb@ ..> wrote:
>
> >
>
> > From: Perry Holcomb <hpholcomb@ ..>
>
> > Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Friday, November 20, 2009, 9:10 PM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > Hey Mark,
>
> >
>
> > No, you can't be certain it'll work.
>
> >
>
> > WO does not recommend the FLAT2 for the M80.  It recommends the FLAT3.  See:
>
> >
>
> > http://www.williamo ptics.com/ accessories/ flattener3_ features. php
>
> >
>
> > However, that does not mean you can't successfully use a non-WO FR/FF with the M80.
>
> >
>
> > Televue makes a respected FR/FF, the TRF-2008.  For that see:
>
> >
>
> > http://www.televue. com/engine/ page.asp? ID=169
>
> >
>
> > The final sentence in the description of the TV FR/FF is,  "Also it can be
>
> > used with any 400-600mm refractor."
>
> >
>
> > Isn't the M80 II triplet somewhere in the high 500mms FL??
>
> >
>
> > Anyway, that's only given as food for thought.  I'm not recommending either because I don't have an M80II.  I'm only mentioning them for possible further research you need to do before buying.
>
> >
>
> > And after that, if you still are somewhat unsure but have made a choice, buy one used!!!!!!!!
>
> >
>
> > Regards, and good luck,
>
> >
>
> > Perry
>
> >
>
> > --- On Fri, 11/20/09, Mark Acker <markacker@yahoo. com> wrote:
>
> >
>
> > From: Mark Acker <markacker@yahoo. com>
>
> > Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Friday, November 20, 2009, 1:56 PM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > So, before I place an order for one, can I be reasonably certain that the FLAT2 will work on an 80mm Megrez II?
>
> > These things seem to be ridiculously hard to find, but I may have a line on one.
>
> >
>
> > Thanks for everyone's patience with this,
>
> > Mark
>
> >
>
> > --- On Wed, 11/18/09, Perry Holcomb <hpholcomb@yahoo. com> wrote:
>
> >
>
> > From: Perry Holcomb <hpholcomb@yahoo. com>
>
> > Subject: Re: [William Optics] Re: Reaching focus on a Megrez
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Wednesday, November 18, 2009, 9:23 AM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > Lynn and all,
>
> >
>
> > The first WO FR/FF, sometimes known as the "I", is designated by the "APO" inscription on the body.  So, it's often known by that.
>
> >
>
> > That was succeeded by the "II", also known as the FLAT2.
>
> >
>
> > That was succeeded by the "III", also known as the FLAT3.
>
> >
>
> > All those were 0.8X reducers.
>
> >
>
> > Then on, ad nauseum...
>
> >
>
> > But the continuing "consumer mystery" here with WO, is what goes with which WO scope? 
>
> >
>
> > Have always found that amusing, especially the way some of these were released touting they were recommended for "X" and "Y" and "Z" WO scopes and then later WO said that no, it wasn't OK for "Z" scope. 
>
> > That's happened more than once, BTW.
>
> >
>
> > Perry
>
> >
>
> > --- On Tue, 11/17/09, kupainter <no_reply@yahoogrou p s.com> wrote:
>
> >
>
> > From: kupainter <no_reply@yahoogrou p s.com>
>
> > Subject: [William Optics] Re: Reaching focus on a Megrez
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Tuesday, November 17, 2009, 8:36 PM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > Mark, it is the older version. The one that WO first came out with. I guess you would call it the I. I have the II, but I use that one on my WO66 so I can get it to come to focus with a SXV guide camera. I think any 0.8x reducer would work for focus. The II and III give a flatter field for larger chips. Some prefer the TeleVue.
>
> >
>
> >
>
> >
>
> > I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x Reducer/Corrector with a Astro Tech AT111ED. For the same reason. To bring to focus and give a F5.6.
>
> >
>
> >
>
> >
>
> > Note, it is important to have the chip the correct distance from the rear of the reducer optics in order to get the best corrected flat field. This varies with different reducers. The older reducer is 52.5 mm. My filter wheel gets me close to that. This only becomes a major issue with larger chips.
>
> >
>
> >
>
> >
>
> > Lynn
>
> >
>
> >
>
> >
>
> > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > >
>
> >
>
> > > Great info.  Did you use the WO FR?  Was this the II or III?
>
> >
>
> > >
>
> >
>
> > > Thanks Lynn,
>
> >
>
> > > Mark
>
> >
>
> > >
>
> >
>
> > > --- On Sun, 11/15/09, kupainter <no_reply@yahoogrou p s.com> wrote:
>
> >
>
> > >
>
> >
>
> > > From: kupainter <no_reply@yahoogrou p s.com>
>
> >
>
> > > Subject: [William Optics] Re: Reaching focus on a Megrez
>
> >
>
> > > To: William-Optics@ yahoogroups. com
>
> >
>
> > > Date: Sunday, November 15, 2009, 9:26 PM
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >  
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > Hi Mark, I have a older Megrez 80 II ED triplet. I use Starlight Xpress Cameras (HX916 and SXVF-H9). They both are 17 mm from the front of the camera to the chip. I could not reach focus with two 2" extension tubes. These telescope tubes are cut short so they can be used with a binoviewer.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > I can reach focus with a 0.8x focal reducer. This shortens the focal length and allows me to reach focus with one 2" extension tube.
>
> >
>
> > >
>
> >
>
> > > This also gives a wider field of view at F5.6.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > Lynn
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.  I am exploring other scope options at the moment, but I won't be making a change immediately.
>
> >
>
> > >
>
> >
>
> > > > The actual issue here is flexure being introduced by the need for 2 extensions.  Am I missing something here or is this a known thing with the Megrez line?  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
>
> >
>
> > >
>
> >
>
> > > > Any insights would be greatly appreciated.
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > Thank you for your thoughts,
>
> >
>
> > >
>
> >
>
> > > > Mark
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>


Reply | Forward | Messages in this Topic (19)
#20576 From: kupainter
Date: Sun Nov 22, 2009 5:09 pm
Subject: [William Optics] Re: Reaching focus on a Megrez--last question 		kupainter
Offline Offline
  
Mark, in choosing the reducer/fastener it's a good idea to consider your chip
size.  I think you said you are using a Meade camera.  What size chip?  With the
older smaller size Meade chips, the field flattest will not be a big issue. 
With larger chips you may get elongated stars in the corners.  My Starlight
Xpresss SXVF-H9 has a 8.95mm x 6.7mm chip.  Small by today's standards.  The
older WO reducer/fastener works fine with the SXVF-H9.  If I use it with a Canon
Rebel, I get elongated stars in the corners.  As I stated in another post, the
suggested distance (lens to chip) is 52.5 mm.  I am close to that with the
SXVF-H9/True Tech filter wheel (53.9 mm).  One can lengthen but one can't
shorten. I was probably way short with the Canon (camera/T ring/reducer) Even
though WO site shows this set-up with their scopes, I don't think it will give
you the optimal distance.

In my WO66 manual there is a ad for the WO reducer/fastener II.  It states
"Suggested lens to chip distance for optimal results is 56mm".  Now, this may
work for the WO66 at F5.9/388FL.
But, it may need to be varied for your scope ( F7/560FL).

I think obtaining correct distance may be the core of the problems people are
having with the reducer/flatteners. Also a number of them are using DSLRs, with
makes it crucial.  Obtaining adapters are not easily available. Which is the
reason WO came out with the adjustable Reducer/Flattener IV.

By the way, I have never used the RF II with any scope other than the WO66/SXV
guider.
The thumb screw on the rotating ring hits the back of my filter wheel.  It would
have to be replaced with a permanent set screw.

Lynn
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
>       Mark,
>
>
>
> Glad I could help.
>
>
>
> For focusing, have you tried a Bahtinov Mask?  I swithed to one from
http://www.focus- mask.com/ and won't leave home without it!  I was using
software that calculated several focus numbers to help maximize the focus.  The
mask is much quicker, more consistent, and results in a better focus.
>
>
>
> If you are handy and have the time this site also has templates to download so
you can cut your own.  The templates are free!
>
>
>
> Tom
>
>
>
> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > Thanks for your thoughts Tom.  You are correct about the Megrez's
numbers.  I was about to give in and get the FLAT3 just because they are
easier, if more expensive, to buy.  I think I am going to just hold out until
I can get the FLAT2 instead.
>
> > Just to reiterate, the initial purpose of this discussion was less to
improve image quality and more to shorten the train back to the camera to
eliminate some flexure.  This seems to have been largely accomplished by just
making sure the focuser tube and rotator screws are tightened fully after
getting focused.  I felt like a dufus when that suggestion was initially
pointed out and it turned out to work beautifully.  Also, by changing the
mount configuration around and eliminating a dual mounting plate and 80mm guide
scope, the balance issue was resolved as well.
>
> >
>
> > Thanks all,
>
> > Mark
>
> >
>
> > --- On Sat, 11/21/09, notgnirramot <notgnirra@ ..> wrote:
>
> >
>
> > From: notgnirramot <notgnirra@ ..>
>
> > Subject: [William Optics] Re: Reaching focus on a Megrez--last question
>
> > To: William-Optics@ yahoogroups. com
>
> > Date: Saturday, November 21, 2009, 7:56 AM
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >       Hi Mark,
>
> >
>
> >
>
> >
>
> > Let me add a little to this discussion.
>
> >
>
> >
>
> >
>
> > I have the Megrez Fluorite Doublet f/6.9 with a focal length of 555mm.  I
image with a Canon Rebel XT DSLR and get very good results with the W/O FLAT2.
>
> >
>
> >
>
> >
>
> > I also have a FluoroStar 110mm f/7.0 with a focal length of 770.  I
purchased a W/O FALT3 for it based on the W/O recommendations on the web site. 
It actually worsens the coma!  I have used the FLAT2 with the FluoroStar with
much better results, not perfect but better than with no flatener.  I will try
the FLAT4 based on correspondence with W/O.
>
> >
>
> >
>
> >
>
> > I have not tried the FLAT3 on my Megrez.
>
> >
>
> >
>
> >
>
> > I believe your scope is the Megrez II ED Triplet which is f/7 with a focal
length of 560mm.  Pretty close numbers to my Megrez.
>
> >
>
> >
>
> >
>
> > The FLAT2 has a good reputation in the DSLR imaging world with many Orion
80ED, fl 600, users showing great success with that reducer flattener.  It seems
to be a very good product for scopes in the size and focal length range of your
scope.
>
> >
>
> >
>
> >
>
> > Plus if you were to get one and decide to try something else there would be
a good market to resell it.  I've not seen a single good reveiw of the FLAT3 and
it might be harder to resell.
>
> >
>
> >
>
> >
>
> > Hope that helps.
>
> >
>
> >
>
> >
>
> > Tom
>
> >
>
> >
>
> >
>
> > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > >
>
> >
>
> > > That ambiguity was what actually led to the question. 
;)   I am going to see if I can get a FLAT3 as that one does
seem to have a higher probability of success.
>
> >
>
> > > Thanks Perry.
>
> >
>
> > >
>
> >
>
> > > --- On Fri, 11/20/09, Perry Holcomb <hpholcomb@ ..> wrote:
>
> >
>
> > >
>
> >
>
> > > From: Perry Holcomb <hpholcomb@ ..>
>
> >
>
> > > Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last
question
>
> >
>
> > > To: William-Optics@ yahoogroups. com
>
> >
>
> > > Date: Friday, November 20, 2009, 9:10 PM
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
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> > >
>
> >
>
> > >
>
> >
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> > >
>
> >
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> > >
>
> >
>
> > >  
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
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> > >
>
> >
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> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >       Hey Mark,
>
> >
>
> > >
>
> >
>
> > > No, you can't be certain it'll work.
>
> >
>
> > >
>
> >
>
> > > WO does not recommend the FLAT2 for the M80.  It recommends the
FLAT3.  See:
>
> >
>
> > >
>
> >
>
> > > http://www.williamo ptics.com/ accessories/ flattener3_ features. php
>
> >
>
> > >
>
> >
>
> > > However, that does not mean you can't successfully use a non-WO FR/FF with
the M80.
>
> >
>
> > >
>
> >
>
> > > Televue makes a respected FR/FF, the TRF-2008.  For that see:
>
> >
>
> > >
>
> >
>
> > > http://www.televue. com/engine/ page.asp? ID=169
>
> >
>
> > >
>
> >
>
> > > The final sentence in the description of the TV FR/FF is,  "Also
it can be
>
> >
>
> > >   used with any 400-600mm refractor."
>
> >
>
> > >
>
> >
>
> > > Isn't the M80 II triplet somewhere in the high 500mms FL??
>
> >
>
> > >
>
> >
>
> > > Anyway, that's only given as food for thought.  I'm not
recommending either because I don't have an M80II.  I'm only mentioning
them for possible further research you need to do before buying.
>
> >
>
> > >
>
> >
>
> > > And after that, if you still are somewhat unsure but have made a choice,
buy one used!!!!!!!!
>
> >
>
> > >
>
> >
>
> > > Regards, and good luck,
>
> >
>
> > >
>
> >
>
> > > Perry
>
> >
>
> > >
>
> >
>
> > > --- On Fri, 11/20/09, Mark Acker <markacker@yahoo. com> wrote:
>
> >
>
> > >
>
> >
>
> > > From: Mark Acker <markacker@yahoo. com>
>
> >
>
> > > Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last
question
>
> >
>
> > > To: William-Optics@ yahoogroups. com
>
> >
>
> > > Date: Friday, November 20, 2009, 1:56 PM
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
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> > >
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> >
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> > >
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> >
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> > >
>
> >
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> > >  
>
> >
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> > >
>
> >
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> > >
>
> >
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> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >       So, before I place an order for one, can I be reasonably certain
that the FLAT2 will work on an 80mm Megrez II?
>
> >
>
> > > These things seem to be ridiculously hard to find, but I may have a line
on one.
>
> >
>
> > >
>
> >
>
> > > Thanks for everyone's patience with this,
>
> >
>
> > > Mark
>
> >
>
> > >
>
> >
>
> > > --- On Wed, 11/18/09, Perry Holcomb <hpholcomb@yahoo. com> wrote:
>
> >
>
> > >
>
> >
>
> > > From: Perry Holcomb <hpholcomb@yahoo. com>
>
> >
>
> > > Subject: Re: [William Optics] Re: Reaching focus on a Megrez
>
> >
>
> > > To: William-Optics@ yahoogroups. com
>
> >
>
> > > Date: Wednesday, November 18, 2009, 9:23 AM
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >  
>
> >
>
> > >
>
> >
>
> > >
>
> >
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> > >
>
> >
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> > >
>
> >
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> > >
>
> >
>
> > >
>
> >
>
> > >       Lynn and all,
>
> >
>
> > >
>
> >
>
> > > The first WO FR/FF, sometimes known as the "I", is designated by the "APO"
inscription on the body.  So, it's often known by that.
>
> >
>
> > >
>
> >
>
> > > That was succeeded by the "II", also known as the FLAT2.
>
> >
>
> > >
>
> >
>
> > > That was succeeded by the "III", also known as the FLAT3.
>
> >
>
> > >
>
> >
>
> > > All those were 0.8X reducers.
>
> >
>
> > >
>
> >
>
> > > Then on, ad nauseum...
>
> >
>
> > >
>
> >
>
> > > But the continuing "consumer mystery" here with WO, is what goes with
which WO scope? 
>
> >
>
> > >
>
> >
>
> > > Have always found that amusing, especially the way some of these were
released touting they were recommended for "X" and "Y" and "Z" WO scopes and
then later WO said that no, it wasn't OK for "Z" scope. 
>
> >
>
> > >  That's happened more than once, BTW.
>
> >
>
> > >
>
> >
>
> > > Perry
>
> >
>
> > >
>
> >
>
> > > --- On Tue, 11/17/09, kupainter <no_reply@yahoogrou p s.com> wrote:
>
> >
>
> > >
>
> >
>
> > > From: kupainter <no_reply@yahoogrou p s.com>
>
> >
>
> > > Subject: [William Optics] Re: Reaching focus on a Megrez
>
> >
>
> > > To: William-Optics@ yahoogroups. com
>
> >
>
> > > Date: Tuesday, November 17, 2009, 8:36 PM
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
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> > >
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> >
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> > >
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> >
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> > >
>
> >
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> > >  
>
> >
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> > >
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> >
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> > >
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> >
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> > >
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> >
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> > >
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> >
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> > >
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> >
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> > >
>
> >
>
> > >       Mark, it is the older version. The one that WO first came out with.
I guess you would call it the I. I have the II, but I use that one on my WO66 so
I can get it to come to focus with a SXV guide camera. I think any 0.8x reducer
would work for focus.  The II and III give a flatter field for larger chips.
Some prefer the TeleVue.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x
Reducer/Corrector with a Astro Tech AT111ED.  For the same reason. To bring to
focus and give a F5.6.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > Note, it is important to have the chip the correct distance from the rear
of the reducer optics in order to get the best corrected flat field.  This
varies with different reducers. The older reducer is 52.5 mm.  My filter wheel
gets me close to that.  This only becomes a major issue with larger chips.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > Lynn
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > Great info.ÃÆ'‚  Did you use the WO
FR?ÃÆ'‚  Was this the II or III?
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > Thanks Lynn,
>
> >
>
> > >
>
> >
>
> > > > Mark
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > --- On Sun, 11/15/09, kupainter <no_reply@yahoogrou p s.com> wrote:
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > From: kupainter <no_reply@yahoogrou p s.com>
>
> >
>
> > >
>
> >
>
> > > > Subject: [William Optics] Re: Reaching focus on a Megrez
>
> >
>
> > >
>
> >
>
> > > > To: William-Optics@ yahoogroups. com
>
> >
>
> > >
>
> >
>
> > > > Date: Sunday, November 15, 2009, 9:26 PM
>
> >
>
> > >
>
> >
>
> > > >
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> >
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> > >
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> >
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> > > >
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> >
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> > >
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> > > >
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> >
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> > >
>
> >
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> > > >
>
> >
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> > >
>
> >
>
> > > > ÃÆ'‚ 
>
> >
>
> > >
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> >
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> > > >
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> >
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> > >
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> >
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> > > >
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> >
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> > >
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> >
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> > > >
>
> >
>
> > >
>
> >
>
> > > > Hi Mark, I have a older Megrez 80 II ED triplet.  I use Starlight Xpress
Cameras (HX916 and SXVF-H9).  They both are 17 mm from the front of the camera
to the chip.  I could not reach focus with two 2" extension tubes.  These
telescope tubes are cut short so they can be used with a binoviewer.
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > I can reach focus with a 0.8x focal reducer.  This shortens the focal
length and allows me to reach focus  with one 2" extension tube.
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > This also gives a wider field of view at F5.6.
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > Lynn
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..>
wrote:
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > >
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > > I know this has been discussed several times in the past, but wow, I
am having a heckuva time imaging with a Megrez II 80mm.ÃÆ'‚  The
camera is a Meade DSI IIIc and in order to reach focus, I have to have the
focuser racked almost all the way out and still need 2-2"
extensions.ÃÆ'‚  The only way I can parfocalize an EP is to go
straight into the second extension without the use of a
diagonal.ÃÆ'‚  I am exploring other scope options at the moment,
but I won't be making a change immediately.
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > > The actual issue here is flexure being introduced by the need for 2
extensions.ÃÆ'‚  Am I missing something here or is this a known
thing with the Megrez line?ÃÆ'‚  Is there a single 4" extension
to be had somewhere or is this some sort of custom job for someone?
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > > Any insights would be greatly appreciated.
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > >
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > > Thank you for your thoughts,
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > > Mark
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>
> > > > >
>
> >
>
> > >
>
> >
>
> > > >
>
> >
>
> > >
>
> >
>

Reply | Forward | Messages in this Topic (19)
#20577 From: Mark Acker <markacker@...>
Date: Sun Nov 22, 2009 7:35 pm
Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question 		markacker
Offline Offline
Send Email Send Email
 
Thank you Lynn.  I came across a focal reducer calculator last night and started messing around with it.  My Meade chip is actually smaller than yours at 6.45x6.45, so the FLAT2 may work just fine, but I am pitching this whole idea for the time being.  I left myself get distracted from the original point which was to reduce flexure due to how far back the camera is.  It turns out that as long as I lock down the focuser rotator screw, it is not really an issue.  I was not doing this in the beginning.  Felt like a real dufus when this was suggested.
I will certainly revisit this later, but almost certainly not until something in the equation changes as I think the Meade/Megrez combo will be with me until I get that SBIG/Tak combo that keeps me awake at night ;).
Thanks so much for all your input on this.

--- On Sun, 11/22/09, kupainter <no_reply@yahoogroups.com> wrote:

From: kupainter <no_reply@yahoogroups.com>
Subject: [William Optics] Re: Reaching focus on a Megrez--last question
To: William-Optics@yahoogroups.com
Date: Sunday, November 22, 2009, 11:09 AM

 

Mark, in choosing the reducer/fastener it's a good idea to consider your chip size. I think you said you are using a Meade camera. What size chip? With the older smaller size Meade chips, the field flattest will not be a big issue. With larger chips you may get elongated stars in the corners. My Starlight Xpresss SXVF-H9 has a 8.95mm x 6.7mm chip. Small by today's standards. The older WO reducer/fastener works fine with the SXVF-H9. If I use it with a Canon Rebel, I get elongated stars in the corners. As I stated in another post, the suggested distance (lens to chip) is 52.5 mm. I am close to that with the SXVF-H9/True Tech filter wheel (53.9 mm). One can lengthen but one can't shorten. I was probably way short with the Canon (camera/T ring/reducer) Even though WO site shows this set-up with their scopes, I don't think it will give you the optimal distance.

In my WO66 manual there is a ad for the WO reducer/fastener II. It states "Suggested lens to chip distance for optimal results is 56mm". Now, this may work for the WO66 at F5.9/388FL.
But, it may need to be varied for your scope ( F7/560FL).

I think obtaining correct distance may be the core of the problems people are having with the reducer/flatteners. Also a number of them are using DSLRs, with makes it crucial. Obtaining adapters are not easily available. Which is the reason WO came out with the adjustable Reducer/Flattener IV.

By the way, I have never used the RF II with any scope other than the WO66/SXV guider.
The thumb screw on the rotating ring hits the back of my filter wheel. It would have to be replaced with a permanent set screw.

Lynn
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> Mark,
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> Glad I could help.
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> For focusing, have you tried a Bahtinov Mask? I swithed to one from http://www.focus- mask.com/ and won't leave home without it! I was using software that calculated several focus numbers to help maximize the focus. The mask is much quicker, more consistent, and results in a better focus.
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> If you are handy and have the time this site also has templates to download so you can cut your own. The templates are free!
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> Tom
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> --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
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> > Thanks for your thoughts Tom.  You are correct about the Megrez's numbers.  I was about to give in and get the FLAT3 just because they are easier, if more expensive, to buy.  I think I am going to just hold out until I can get the FLAT2 instead.
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> > Just to reiterate, the initial purpose of this discussion was less to improve image quality and more to shorten the train back to the camera to eliminate some flexure.  This seems to have been largely accomplished by just making sure the focuser tube and rotator screws are tightened fully after getting focused.  I felt like a dufus when that suggestion was initially pointed out and it turned out to work beautifully.  Also, by changing the mount configuration around and eliminating a dual mounting plate and 80mm guide scope, the balance issue was resolved as well.
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> > Thanks all,
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> > Mark
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> > --- On Sat, 11/21/09, notgnirramot <notgnirra@ ..> wrote:
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> > From: notgnirramot <notgnirra@ ..>
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> > Subject: [William Optics] Re: Reaching focus on a Megrez--last question
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> > To: William-Optics@ yahoogroups. com
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> > Date: Saturday, November 21, 2009, 7:56 AM
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> > Hi Mark,
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> > Let me add a little to this discussion.
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> > I have the Megrez Fluorite Doublet f/6.9 with a focal length of 555mm. I image with a Canon Rebel XT DSLR and get very good results with the W/O FLAT2.
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> > I also have a FluoroStar 110mm f/7.0 with a focal length of 770. I purchased a W/O FALT3 for it based on the W/O recommendations on the web site. It actually worsens the coma! I have used the FLAT2 with the FluoroStar with much better results, not perfect but better than with no flatener. I will try the FLAT4 based on correspondence with W/O.
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> > I have not tried the FLAT3 on my Megrez.
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> > I believe your scope is the Megrez II ED Triplet which is f/7 with a focal length of 560mm. Pretty close numbers to my Megrez.
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> > The FLAT2 has a good reputation in the DSLR imaging world with many Orion 80ED, fl 600, users showing great success with that reducer flattener. It seems to be a very good product for scopes in the size and focal length range of your scope.
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> > Plus if you were to get one and decide to try something else there would be a good market to resell it. I've not seen a single good reveiw of the FLAT3 and it might be harder to resell.
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> > Hope that helps.
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> > Tom
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> > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
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> > > That ambiguity was what actually led to the question.  ;) Â  I am going to see if I can get a FLAT3 as that one does seem to have a higher probability of success.
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> > > Thanks Perry.
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> > > --- On Fri, 11/20/09, Perry Holcomb <hpholcomb@ ..> wrote:
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> > > From: Perry Holcomb <hpholcomb@ ..>
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> > > Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
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> > > To: William-Optics@ yahoogroups. com
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> > > Date: Friday, November 20, 2009, 9:10 PM
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> > > Hey Mark,
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> > > No, you can't be certain it'll work.
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> > > WO does not recommend the FLAT2 for the M80.  It recommends the FLAT3.  See:
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> > > http://www.williamo ptics.com/ accessories/ flattener3_ features. php
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> > > However, that does not mean you can't successfully use a non-WO FR/FF with the M80.
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> > > Televue makes a respected FR/FF, the TRF-2008.  For that see:
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> > > http://www.televue. com/engine/ page.asp? ID=169
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> > > The final sentence in the description of the TV FR/FF is,  "Also it can be
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> > > used with any 400-600mm refractor."
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> > > Isn't the M80 II triplet somewhere in the high 500mms FL??
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> > > Anyway, that's only given as food for thought.  I'm not recommending either because I don't have an M80II.  I'm only mentioning them for possible further research you need to do before buying.
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> > > And after that, if you still are somewhat unsure but have made a choice, buy one used!!!!!!!!
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> > > Regards, and good luck,
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> > > Perry
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> > > --- On Fri, 11/20/09, Mark Acker <markacker@yahoo. com> wrote:
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> > > From: Mark Acker <markacker@yahoo. com>
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> > > Subject: Re: [William Optics] Re: Reaching focus on a Megrez--last question
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> > > To: William-Optics@ yahoogroups. com
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> > > Date: Friday, November 20, 2009, 1:56 PM
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> > > So, before I place an order for one, can I be reasonably certain that the FLAT2 will work on an 80mm Megrez II?
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> > > These things seem to be ridiculously hard to find, but I may have a line on one.
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> > > Thanks for everyone's patience with this,
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> > > Mark
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> > > --- On Wed, 11/18/09, Perry Holcomb <hpholcomb@yahoo. com> wrote:
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> > > From: Perry Holcomb <hpholcomb@yahoo. com>
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> > > Subject: Re: [William Optics] Re: Reaching focus on a Megrez
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> > > To: William-Optics@ yahoogroups. com
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> > > Date: Wednesday, November 18, 2009, 9:23 AM
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> > > Lynn and all,
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> > > The first WO FR/FF, sometimes known as the "I", is designated by the "APO" inscription on the body.  So, it's often known by that.
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> > > That was succeeded by the "II", also known as the FLAT2.
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> > > That was succeeded by the "III", also known as the FLAT3.
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> > > All those were 0.8X reducers.
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> > > Then on, ad nauseum...
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> > > But the continuing "consumer mystery" here with WO, is what goes with which WO scope? 
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> > > Have always found that amusing, especially the way some of these were released touting they were recommended for "X" and "Y" and "Z" WO scopes and then later WO said that no, it wasn't OK for "Z" scope. 
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> > > That's happened more than once, BTW.
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> > > Perry
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> > > --- On Tue, 11/17/09, kupainter <no_reply@yahoogrou p s.com> wrote:
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> > > From: kupainter <no_reply@yahoogrou p s.com>
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> > > Subject: [William Optics] Re: Reaching focus on a Megrez
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> > > To: William-Optics@ yahoogroups. com
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> > > Date: Tuesday, November 17, 2009, 8:36 PM
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> > > Mark, it is the older version. The one that WO first came out with. I guess you would call it the I. I have the II, but I use that one on my WO66 so I can get it to come to focus with a SXV guide camera. I think any 0.8x reducer would work for focus. The II and III give a flatter field for larger chips. Some prefer the TeleVue.
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> > > I haven't used the WO Megrez II ED in awhile. I am now using the WO 0.8x Reducer/Corrector with a Astro Tech AT111ED. For the same reason. To bring to focus and give a F5.6.
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> > > Note, it is important to have the chip the correct distance from the rear of the reducer optics in order to get the best corrected flat field. This varies with different reducers. The older reducer is 52.5 mm. My filter wheel gets me close to that. This only becomes a major issue with larger chips.
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> > > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
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> > > > Great info.ÃÆ'‚  Did you use the WO FR?ÃÆ'‚  Was this the II or III?
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> > > > Thanks Lynn,
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> > > > --- On Sun, 11/15/09, kupainter <no_reply@yahoogrou p s.com> wrote:
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> > > > From: kupainter <no_reply@yahoogrou p s.com>
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> > > > Subject: [William Optics] Re: Reaching focus on a Megrez
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> > > > To: William-Optics@ yahoogroups. com
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> > > > Date: Sunday, November 15, 2009, 9:26 PM
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> > > > ÃÆ'‚ 
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> > > > Hi Mark, I have a older Megrez 80 II ED triplet. I use Starlight Xpress Cameras (HX916 and SXVF-H9). They both are 17 mm from the front of the camera to the chip. I could not reach focus with two 2" extension tubes. These telescope tubes are cut short so they can be used with a binoviewer.
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> > > > I can reach focus with a 0.8x focal reducer. This shortens the focal length and allows me to reach focus with one 2" extension tube.
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> > > > --- In William-Optics@ yahoogroups. com, Mark Acker <markacker@ ..> wrote:
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> > > > > I know this has been discussed several times in the past, but wow, I am having a heckuva time imaging with a Megrez II 80mm.ÃÆ'‚  The camera is a Meade DSI IIIc and in order to reach focus, I have to have the focuser racked almost all the way out and still need 2-2" extensions.ÃÆ'‚  The only way I can parfocalize an EP is to go straight into the second extension without the use of a diagonal.ÃÆ'‚  I am exploring other scope options at the moment, but I won't be making a change immediately.
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> > > > > The actual issue here is flexure being introduced by the need for 2 extensions.ÃÆ'‚  Am I missing something here or is this a known thing with the Megrez line?ÃÆ'‚  Is there a single 4" extension to be had somewhere or is this some sort of custom job for someone?
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Reply | Forward | Messages in this Topic (19)
#20578 From: "steveb" <bullfox55@...>
Date: Fri Nov 27, 2009 7:43 am
Subject: Flatener Trade 		bullfox55
Offline Offline
Send Email Send Email
  
I have a Flatener III that I would like to trade for a flatener II.

Reply | Forward | Messages in this Topic (1)
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