M 101 synthetic luminance

[DaveS]

This is the result of "polishing a turd"

Over the "nights" of the 2nd, 3rd, and 4th June I captured 18 subs each of RGB with the reconstituted ODK 12 / G3 16200 rig, After fighting the rubbish data for a couple of days I decided to forget about colour and just stack all 54 subs with a Master Dark. After cropping and gradient removal BlurX and NoiseX were applied in PI, then two rounds of Histogram Stretch with a DDP in between in AstroArt 8.

Saved as a PNG.

I had to hammer the background down much further than I would like, and it's still horrible. Moral of the story: don't try to image a low surface brightness galaxy under rubbish conditions. the combination of nautical dark, near full moon, and clag raised my normal mid Bortel 3 sky to more like 8-9.

[rl]

Turd expertly polished! What sort of lap did you use??

Murphy's law in action, I'm afraid. No chance of a supernova in December at new moon while the streetlights are out of action for maintenance....

That is a better result than I got under Bortle 4 skies....

[tomato]

This run of “clear” nights are indeed frustrating. I have always advocated to image under less than ideal conditions but these recent nights are near the bottom of the pile in my experience. This was confirmed when I recently got the 16” Dob out to evaluate the Celestron Starsense unit. It put M13 right in the FOV but I couldn’t find M51 in the scope.

[DaveS]

Sunsets lately have been downright filthy orange, you can see the horrid clag in the air.