So, despite getting my new short and fast refractor and NEQ6, I have spent some time trying to get my venerable old 8" LX200 GPS to take an image longer than 20s. I've put it on a wedge, done the Petersons Bucks Gears upgrade and added guiding through a guide scope. I got my first image from the set up on Sunday and I think while its promising there are still a few issues I need to resolve. Its noisy and I need to start dithering to get rid of some of the banding. I think the guiding was not awful (total RMS around 1.2" most of the time) but I know I can improve on that.
The biggest problem is what looks to me like horrible field curvature and
coma. (Is that what I'm seeing or is it something else) I have a Meade 6.3
FR/
FF in place and had really hoped it would be better but I'd like to hear your thoughts. Is this is good as I'm going to get in terms of flattening, or can I adjust (spacing for example) or do I need to tighten up my colimation. Any thoughts anyone?
Anyway here it is (I know its not great but putting it here to get advice)
8" LX200GPS
f/6.3
FR/
FF, wedged LX200 mount
EOS 1100D (un moded)
Guided in PHD2, Processed
APP (this is not a full process - a very slight crop to remove some ragged edges and a quick run through
APP- I think it could be improved but I'm not sure its worth the effort)
49 X 180s ISO800
So, thanks for looking and any suggestions or advice you can give (preferably not "stay with the 80ED and stick that hulk in a dumpster". I'm Scottish and therfore am genetically programmed to not throw things away!
)
David
Scope: Skywatcher Evostar 80ED (SW 0.85 FR/FF) on a SW NEQ6Pro
Guiding; SW Evoguide 50ED, ASI 120mm mini
Meade 8" LX200 GPS on wedge (Guided with a cheapo 50mm guidescope and a ZWO ASI 120mm mini)
Sharpstar 61EDPH II (with dedicated 0.8 reducer) with wiliam Optics 32mm uniguide
Camera: ASI2600MC pro. QHY 163M with ZWO 7nm NB filters, Canon EOS700D astro mod
Secondary mount: Skywatcher StarAdventurer
My Astrobin
https://www.astrobin.com/users/mackiedlm/