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Originally Posted by Dave882
Thanks Chris and really appreciate your input. I did check the collimation as best as I could (seeing limited of course) and looks pretty good. Nailing focus with the c14 is seriously like shooting at a moving target. When the temp is dropping I do a refocus on nearby star with bahtinov mask every 1hr and even then it’s moved quite a bit. I have a zwo eaf in the back of the cupboard somewhere but still haven’t had time to work out how to get it all connected. Just bing lazy I guess lol.
As I mentioned to Allan my post processing is really basic. No star reduction or masks so unfortunately that’s going to work against me. This was my first time since about Sept22 having my f7 image train going so also got some tilt issues to deal with too (hence the crop image). Anyways I think I’ll have another shot at a repro soon and perhaps even bite the bullet and get PI to get the most from the data.
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I'm definitely not the most experienced astrophotographer, so there is a better than average chance that you already know or use the things I'm about to suggest, but here goes.
I think that that focus and collimation on a cat are critical to getting the detail into an image. It's easy to get 90% of best focus and collimation, but that last 10% is where maybe 50% of the fine detail lives.
I use a tri-bahtinov mask and touch up the collimation maybe twice or more a night, pre and post meridian due to minor mirror flop. The tri-b mask makes it so much easer to hit optimum collimation.
You're already using an ASIAIR pro and with the EAF attached you can set the autofocus to trigger on temperature changes or every hour while in Autorun. I would also use Star Detect (i think thats what it was called, I no longer use Asiair) which will display the average HFR in an image. During autorun I would run Star Detect on images and if HFR had increased by maybe 10% I would manually trigger an autofocus.
If you're still using the original focus control, make sure the focus, either auto or by hand, finish with the mirror moving in, otherwise the mirror will slowly relax back under gravity over time. There is a reverse selection for the EAF, again from memory it has to be selected to "reverse" so that focus finished going in.
Chris