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Yes, another M81


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... This is actually my first image taken using my new AVX mount.  Still the same Celestron Nexstar 8" with a .63 focal reducer.  I have incorporated an ASIAir Plus and while it does have a learning curve, the experience is transformative.  The less time I spend trying to manage cables and various pieces of software, the more I have to image and learn the post-processing bit!   Main camera is a ASI294MC Pro, cooled to -10C.  Guide camera is a ASI290MM in a SVbony 60mm guidescope.  Dithered 2 px every 3 frames (still experimenting here). I found the guiding was actually pretty spot-on - I think it could have improved with a bit better focus.   Same with the main camera - I used a bahtinov mask, but I suspect the focus shifted over time.  Seeing was average.

 

100 x 180 sec lights w uv/ir cut filter only.  Might try an LP filter next time, that might help with a bit of the noise.  I didn't want to go any blacker on the background.  30x each darks, flats, biases.  Stacked in DSS, processed in Siril and GIMP for levels and contrast mostly.  Thanks for looking!

 

image.thumb.jpeg.f7a9852f5887292654e9a50a3dd8eba9.jpeg

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Very nice round stars. I dither every frame when doing subs over a minute. On shorter subs I do it every 5 frames. On bright objects like this galaxy you might be better decreasing exposure time doing 30 second subs and many of them. When stacked the dusty bits will be apparent and you won't get blow out of the bright core. 

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