PDA

View Full Version here: : Ngc 7755


rogerg
14-09-2006, 10:12 AM
This is a very nice face-on galaxy that I stumbled upon. My image doesn't really do it justice.

I had quite poor viewing conditions (not sure why, but while it's been clear the last few nights it's also been very turbulent). And the moon rose just after midnight, together with the object crossing the meridian at the same time. So none of the images after midnight were usable but that was expected.

I've been having trouble with plate solving lately, seems to only occasionally work, so I'm not able to reliably automated it to move between objects, so I just leave it taking the same object all night regardless of the conditions/moon/focus. I would have scripted a re-focus, but it was choosing to re-focus on the galaxy which wasn't doing a lot of good for it's accuracy!

I hope to re-process it soon, there's much more outer faint detail in the raw images, just a case of getting it and not the noise in the processed images.

I took 15 x 1200sec but only used 7 x 1200 sec.

http://www.rogergroom.com/rogergroom/esh_rog_item.jsp?Item=422

Roger.

EzyStyles
14-09-2006, 12:21 PM
very nice Roger. That is one hard galaxy to capture and you did it nicely.

tornado33
14-09-2006, 12:38 PM
Yes thats a nice galaxy, and one ive not seen before, well done.
Scott

h0ughy
14-09-2006, 12:57 PM
wow, how'd you get the f7.5 focal length?

rogerg
14-09-2006, 01:09 PM
Thanks guy's. F/7.5 is what my setup happens to land at when I put the F/6.3 reducer on (calculated using Astrometrica to plate solve the FOV).

I think I've mentioned before how I need one of these things:
http://www.ziplink.net/users/lester/FLR.html

Because I have my NGF-C w/RoboFocus between scope rear cell and the F/6.3 reducer, the focal length changes quite dramatically. And I get problems with distortions etc (you can see the slightly illongated stars). I also have problems with the camera hanging way off the back of the scope, but only as far as it limiting how far south I can point.

It's even more of a problem if I wanted to put the 350D on there prime focus, I think I'd end up with tones of distortion and huge problems with overhang.

One of these days I'll decide I can spare the $200 for the thing linked above :)

Roger.

Striker
14-09-2006, 02:27 PM
Nice faint Galaxy Roger.

I know exactly what you mean regarding over hang being a problem.