Sh2-86 in Colour

[Astrodoc]

This image uses the 8 hr of Ha data posted yesterday along with 5.5 hr RGB data collected a few weeks ago.  All pre-processing and processing in PixInsight.

http://astrodoc.ca/sh2-86-emission-nebula-colour/

Thanks for looking, and I hope you enjoy it!

Clear skies,
Ron

[Jason Tackett]

Very nice work! I like how your processing steps are not very aggresive and yield such good contrast in the nebulosity. The yellow stars also stand out well. I see you used ACDNR twice - once targeting small scales before HT and again after HT targeting large scales in the background. Did you use the standard deviation in the ACDNR process to target these scales or some other setting? This seems like a good idea. I was just curious about the rationale. Thanks for sharing!

Jason

[Astrodoc]

I use the standard deviation slider to adjust scale.  First I use small scale NR (around 0.8-1.2 px scale) with a very light mask for luminance to provide overall noise reduction to the image (chrominance around 1-1.6 px scale; no mask).  Then, after resetting the black point, I apply noise reduction with a larger scale (4-6 px luminance; 5-7 chrominance) and use quite a dark mask (on both luminance and chrominance) to limit this step to the lowest signal regions of the image.

Clear skies,
Ron

[Jason Tackett]

Thanks for the details. That seems like an effective procedure to lower noise globally and then aggressively in the background.