Hi Ron, Am not familiar with the term capture ratio. Or is that analogous to f-ratio? - so larger pixels would rob you of resolution but allow you to take ...
72453
Stan
stan_ccd
Mar 12, 2013 6:30 pm
... Well I think you are also doing a pretty good job of that with your perhaps overly elaborate calculations! ... You forgot an essential part of that...
72454
turnerjs085
Mar 12, 2013 6:57 pm
Hi, I am not sure if this is the right place for this question, but I am stumped and not really sure where to start. Here it goes; I am using the qsi wsg...
72455
Ken Harrison
ken4optics
Mar 12, 2013 7:11 pm
Jeremy, Hmmmm One thing comes to mind. If the guide chip is 17mm from the optical axis, then maybe the edge of the field in suffering vignetting from the...
72456
Bernard Miller
bgmiller_01
Mar 12, 2013 7:45 pm
Hi, The link below is to NGC1333. This is a reflection nebula in the constellation Preseus. Except for the central blue region, the rest of the nebula is very...
72457
Orlando Andico
orly_andico
Mar 12, 2013 7:46 pm
So here's another situation which has me scratching my head. The older Kodak sensors (e.g. KAF-1603..) are rated at 0.9 e-/sec dark curent at 0 Celsius. Now...
72458
Ron Wodaski
rwodaski
Mar 12, 2013 7:55 pm
Signal and noise don't work that way, you'll be glad to know. :-) The relationship is quadratic, not linear, and so longer exposures will (slowly) drive down...
72461
Stan
stan_ccd
Mar 12, 2013 9:34 pm
... Or expose long enough to improve the S/N as necessary. Whatever the S/N is for a given exp it will improve by 1.4x for every doubling of exp time (assuming...
72462
turnerjs085
Mar 12, 2013 11:52 pm
that is what i will do tonight. I have used it at f10 before, but is has been a while and i cant remember if i used a guidescope or not. I am guessing it is a...
72463
Steve C. Mitchell, Sr...
eyecenter1000
Mar 13, 2013 5:14 am
Very nice Bernard! Like looking down the throat of a blue eyed monster! 8>) The reds are awesome. ~20 hours! That's perseverance. Steve Stephen C. Mitchell,...
72464
John
jabberwock48
Mar 13, 2013 2:53 pm
I have very much the same setup although with an Optec Pyxis between the Lepus and the QSI and with a TCF-s focuser. Looking at a flat when using a T adapter...
72465
jeffreyjongmans
Mar 13, 2013 8:06 pm
I spend two nights on this one. The first night everything that could go wrong, went wrong. My flatfield panel broke down, CCDAutoPilot was determined to guide...
72466
Bob Runyan
runrob68876
Mar 13, 2013 8:29 pm
Hello Jeffrey: IMYO, I would give this one APOD consideration. Especially for the size scope you are using. Not over cooked and great resolution. Bob R. ... ...
72467
Bernard Miller
bgmiller_01
Mar 14, 2013 2:55 am
Jeff, Very nice result. I think the color and detail are great. Bernard From: ccd-newastro@yahoogroups.com [mailto:ccd-newastro@yahoogroups.com] On Behalf Of...
72468
Orlando Andico
orly_andico
Mar 14, 2013 3:05 pm
this is a bit related to my queries yesterday. Here's my situation: I live in an extremely light-polluted location. I accept that AP under these conditions is...
72469
Stan
stan_ccd
Mar 14, 2013 4:14 pm
... Not entirely. Your best bet is to image nebula with narrow band filters. They are great equalizers in that they remove nearly all sky pollution while...
72470
Stan
stan_ccd
Mar 14, 2013 5:41 pm
... That was a typo, I meant 6-10 fold: a high quality H-a filter will pass 98% of H-a, whereas that stack probably passes 85% at best, thus the signal would...
72471
Orlando Andico
orly_andico
Mar 14, 2013 5:42 pm
Thanks Stan. I was expecting that a mono camera would be the recommendation. This guy's results though are different - http://www.helixgate.net/XMvsXCM2.html ...
72472
Ron Wodaski
rwodaski
Mar 14, 2013 5:47 pm
Those images are stretched, which is somewhat misleading when comparing them. The whole point of a better exposure is that if you are going to stretch it, you...
72473
Orlando Andico
orly_andico
Mar 14, 2013 5:50 pm
Stan, I don't understand the part about the true mono camera being 4X as sensitive. I understand that for a given aperture, the object gets projected onto the ...
72474
Orlando Andico
orly_andico
Mar 14, 2013 5:50 pm
Thanks Ron. You are right, it's hard to see dynamic range. :D I'll take your word for it. So the next question is.. which mono camera? is QE that...
72475
Ron Wodaski
rwodaski
Mar 14, 2013 6:02 pm
The short answer would be that a mono camera would have 4x the pixels, so would capture 4x the light. Both chips have the same _total area_, it's just that 3/4...
72476
Ron Wodaski
rwodaski
Mar 14, 2013 6:10 pm
Well, it's only hard because it's unfamiliar. You can train yourself to see the differences that relate to dynamic range. <g> Re: which mono camera? How much...
72477
Stan
stan_ccd
Mar 14, 2013 6:14 pm
... Not really. His setups are equivalent (same filter efficiency and pass band) so that the Bayer matrix is the primary variable. A 4x difference in...
72478
Stan
stan_ccd
Mar 14, 2013 6:19 pm
... The true mission and metric of a camera is how much information it can capture from the virtual image presented to it. Photons = information and basic...
72479
Stan
stan_ccd
Mar 14, 2013 6:26 pm
... Actually I meant 4x more sub-exps to produce 4x longer total exp. Taking longer sub-exps for only one camera would unbalance the affects of read noise and...
72480
Orlando Andico
orly_andico
Mar 14, 2013 6:39 pm
Thanks for the reply, Ron. Sadly, I am not made of money, so those fancy back-illuminated chips are out. This is after all a hobby. So.. if I'm looking at a...
72481
Orlando Andico
orly_andico
Mar 14, 2013 6:40 pm
There is another option that obviously appeals to the penny-pincher (and DIY'er) in me. An equipment liquidator on ebay is selling these old Quantix microscopy...
72482
Stan
stan_ccd
Mar 14, 2013 7:45 pm
... This can be a great deal (I obtained a used microscopy EMCCD from a similar liquadator for 10% of retail). I didn;t look at that one, but most of lab CCDs...
72483
Orlando Andico
orly_andico
Mar 15, 2013 12:36 am
Hi Stan, These microscopy cameras use a PCI interface, and they come with their own capture software BUT can also be driven by MaximDL Pro. A desktop or laptop...
