Hello, In the message below Richard described the seeing quality in terms of arc-seconds. How does one make that kind of measurement? Is it a feature of the...
29002
Rob Miller
force9boat
Jun 30, 2004 5:25 am
In the message below Richard described the seeing quality in terms of arc-seconds. How does one make that kind of measurement? Is it a feature of the SBIG...
29003
rdcrisp
Jun 30, 2004 5:41 am
... Hi Rob Actually the measurement is pretty easy. I know my plate (image) scale to be about 1.1 arc-seconds per pixel. You can calculate that quite readily. ...
29004
Richard Bennion
rbennion
Jun 30, 2004 6:35 am
Mike, Welcome to the group. Your images are wonderful. You also certainly have the equipment to do the work. There are few of us who have quite a bit of...
29005
Mark de Regt
soccernutsea...
Jun 30, 2004 6:47 am
Rob, I use AIP4WIN to do it; it has a star image tool, which measures the FWHM of stars, in pixels. I know the image scale at which I image (using image link...
29006
Mark de Regt
soccernutsea...
Jun 30, 2004 6:48 am
Donald, That's a nice image. I would decrease saturation a bit, but that's a personal preference. Your focus may be a bit soft, or your seeing may have been...
29007
Mark de Regt
soccernutsea...
Jun 30, 2004 6:48 am
Mike, Welcome! I think I recognize your name from MAPUG; I kind of carry the torch for the LX200 around here, so you should feel quite welcome. You've made a...
29008
Astrofx@...
txskywatcher
Jun 30, 2004 11:29 am
Richard Nice job with this dim portion of the Pelican. That is "up close and personal". For the first time I really noticed the very end (faint) extension that...
29009
Donald Waid
donwaid
Jun 30, 2004 12:09 pm
Mark, Thanks for your comments. The skies are pretty dark at my Oklahoma site but the seeing is typically not as good as one would like. The jet stream was...
29010
Don Waid
donwaid
Jun 30, 2004 2:36 pm
Hey Mark, There are a few other avid LX200 types here! I have 3 of them. <G> Don http://www.waid-observatory.com ... From: Mark de Regt To:...
29011
Dennis Persyk
dennis_persyk
Jun 30, 2004 3:30 pm
The two commonly used methods by serious imagers are DIMM and single star displacement. DIMM stands for differential image motion monitor. A Hartmann mask is...
29012
Tim Long
t_p_long
Jun 30, 2004 4:27 pm
I don't know about your specs, but if you're going to be taking a lot of dark and bias frames for use with Sigma, then you might find my DarkManager program...
29013
rdcrisp
Jun 30, 2004 4:55 pm
... The good thing about doing it the simple way is that is what you wind up with on your image. It is interesting to know what the "seeing" is, but once a...
29014
Dennis Persyk
dennis_persyk
Jun 30, 2004 5:15 pm
Hi Richard, I'm all for simple, so help me out. It sounds like you have been successful in using PSF measurements. I live in the Midwest where seeing is...
29015
rdcrisp
Jun 30, 2004 5:25 pm
... and ... I'm just a hack and make my measurement on the star I use for focusing. It changes from day to day depending on my target. I've been doing it...
29016
Mark de Regt
soccernutsea...
Jun 30, 2004 6:22 pm
Don, There are quite a number of us LX200 types here; sometimes I'm just the most vocal in defending it as a quality imaging platform. --Mark...
29017
Ron Brant
astroron2001
Jun 30, 2004 6:25 pm
I agree Richard, it's the day to day real world that matters. Science, that's one thing, photos, that's another! Ron B. ... From: rdcrisp To:...
29018
erdmanpe
Jun 30, 2004 6:33 pm
In the various example seeing numbers you mention, have you already removed your best guess of the PSF, or are you refering to the convolution of the two? ...
29019
Wodaski Yahoo
rwodaski
Jun 30, 2004 7:29 pm
This looks better with a more restrained histogram. More subtlety visible in the low-contrast areas. Colors spot on. If the wind is out of the west, and I...
29020
rdcrisp
Jun 30, 2004 7:57 pm
... The latter. All I am doing when I quote a number is telling you what I read from FocusMax or alternatively what I read from Maxim when I slide my cursor...
29021
erdmanpe
Jun 30, 2004 8:55 pm
Same here, I was just wondering if you were doing it any differently. Peter...
29022
rhoowl@...
rhoowl
Jun 30, 2004 9:38 pm
HI everyone new member here....just looked over the photo section...some really great images in there...hope to be doing the same.... jamie ...
29023
Michael Sherick
michaelsherick
Jun 30, 2004 9:43 pm
Hello Group, I'm wondering if anyone in the Group is using a 16" to 20" classical cassegrain scope for CCD imaging? If so, could you comment on the focal...
29024
David
starts_with_d
Jun 30, 2004 11:08 pm
Greetings, I am planning on building a f5 12.5" dobsonian for visual use and ccd photography. One of my considerations is whether I will use a dual-axis...
29025
Wodaski Yahoo
rwodaski
Jun 30, 2004 11:21 pm
It is easier to build a robust, accurate, and precise equatorial platform than it is to do the same with an instrument rotator. Some reasons: * You can't just...
29027
Lenny Shaffer
lenny_shaffer
Jul 1, 2004 12:44 am
One of the most detailed explanations you can find on Mels' system is here: http://www.ghgcorp.com/cshaw/14newt.htm and Mel's list of links is here: ...
29028
Charlie Warren
txskywatcher
Jul 1, 2004 1:34 am
Imaging widefield Ha is sure a lot of fun. This is another from the last Chiefland visit. The Ha seemed to cut through some of the haze. I did get some very...
29029
Michael Sherick
michaelsherick
Jul 1, 2004 3:09 am
Hello David, I too had an interest in doing what you mentioned. I built up a 17.5" dobsonian using Kriege's book. I then configured it with an Argo-Navis...
29030
Michael Cole
urbanimager
Jul 1, 2004 4:41 am
Nice Clean image Charlie. Good detail. Michael Cole UrbanImager Astrophotography website http://home.earthlink.net/~urbanimager/index.htm ... -- [Non-text...
29031
Ron Wodaski
rwodaski
Jul 1, 2004 5:16 am
The pelican nebula isn't what you usually think of when you think of imaging at the full moon. H-alpha, lunar imaging, and globular clusters are more typical...
