|
I agree Rob - it is nice to be able to control the dithering rather than have the edge of your well framed image chopped off due to drift.
I've been keeping a spreadsheet log (using Deepsky Stacker's calculated dx and dy numbers) for each change I've made to my setup as I've tried to eliminate the source of my flexure. Being a side by side setup there are a few more variables and I'm now down to dx (RA drift only). The guide scope I now use has a helical focuser, my newt now has a moonlight focuser, I've changed to heavier bob's knobs springs and losmandy dovetails throughout and to a heavier Starstuff SBS bar.
I started up with 0.6-1.0 pixel per minute drift and now have this down to 0.1-0.3. Changing from 0.8 pixels per minute to 0.2 means each sub can be 4 times the duration without the stars becoming elongated. Previously I was constrained to 1 min subs but now routinely use 5 mins.
Most recently I've changed to heavier Parallax rings for the newt however the weather has been poor since they arrived so I don't know if this has had any impact yet.
I polar align using Alignmaster and then check with k3ccd tools drift alignment analyzer so I know my issue is not polar alignment.
Peter
|