A couple of humble attempts from the weekend - whilst I'm waiting for my new toys.
This was shot with the WO 70mm scope, Televue Reducer, piggybacked on the LX-90. Focusing was with a Bahtinov mask - I don't think it was perfect with Eta Carina, but I was happier with it on NGC4945.
They were guided through the 8inch OTA at 2000mm focal length - the guiding graph was pretty erratic, but I wasn't prepared to spend a lot of time fiddling with settings when this will hopefully be the last time I image with this mount. (The periodic error was +/-20arcsec). The seeing was pretty average.
The camera is an unmodded Nikon D200 - 5 min subs. 20mins of exposures for NGC4945 & 35mins for Eta Carina. They were stacked in DSS with a dozen dark frames. I then stretched the image in PS and bumped the saturation for Eta Carina. Both are cropped.
What length of exposure was each light frame for eta carina? At iso 800, and a 5 min exposure there should heaps more data there to play with. Were you in light polluted skies?
I'm wondering if I am suffering from a problem with darks. I took these darks at a later time. The camera does get hot when exposing for the dark frames and you can visibly see a rise in noise as you scroll through them.
I would go back and check your setting in DeepSkyStacker. Perhaps you processed the darks as 'lights' or something like that might have happened by mistake.
James
No David - Nikon sensors aren't bad at all! Here's an examle of a 300-sec shot from my trusty little D40 (unmodded) at ISO800 and your current Tak FS-102. It's the result of stacking (manually in Photoshop CS3) one each of single 300-sec, 30-sec and 15-sec frames. No more.
If you'd like, could you email me a few of your subs?
I chose the dark frames (ie. the ones taken when the sensor was a bit cooler) and tried again.
I think I was using median combine last night. I tried median combine again and kappa "something or other" (it's late and I was out at work for 14hrs today).
The attached file is with selected darks and median combine.
Is there anywhere that explains these combination methods and suggests what to do with DSS.
I have a trial of Maxim DL, but haven't really tried to use that. I can't capture >30sec exposures directly into Maxim without spending lots of dollars on a special cable for Nikon. Does Maxim load Nikon RAW files?
Thanks again for looking.
It's starting to dawn on me that there is an awful lot to learn about post-processing..................
