20211105 - Melotte 15 CAS - The Heart of the Heart - Into the heart of darkness … (SHO)

What’s in the picture(s)
Melotte 15 - The Heart of the Heart
Quote: “The Heart nebula, also known as Index Catalog IC-1805, Sharpless 2-190, with Melotte 15 open star cluster lies some 7500 light years away from Earth and is located in the Perseus Arm of our Milky Way Galaxy in the constellation Cassiopeia. It was discovered by William Herschel on 3 November 1787. This is an emission nebula showing glowing ionized hydrogen gas and darker dust lanes.”

What was the experience
It had been clouds for weeks … until just one night. The chance to try something new. Instead of the standaard rgb, I wanted to image a real SHO palette for once. The difficulty was however in the processing: how is this sho-image supposed to look? It seems it is a matter of taste ….

Color calibration is intended for rgb-images, but SHO is showing different colours, with many different possible combinations of the channels, sometimes ending up with eerie red stars against a hard green and blueish backdrop.

With some tutorials to the rescue, the processing on this image has helped to expand my range of PixInsight skills. It was done as a straight SHO combination, with Ha serving as the main luminance channel, green removal with SCNR, tweaking the curves for rgb, sat and hue, running ACDNR, dark structure enhancement, Local histogram, and also the EZ-suite. Trying out all tweaks, to determine what my favourite colour palette should be, currently settling for this one … a bit hard on the colours and the saturation, but that’s my current mood

Somehow the image ended up a bit dark. Maybe I need to “lighten the heart” a bit in a next processing pass 😉

How it was done
Scope: TS-140 APO (FL 910mm)
Mount: CEM70G
Camera: ASI2600MM Pro
Filter: Baader
Photons:  300s LSHO 9x 10x 20x 10x
Bortle 5/6
Processing: PixInsight (Mac)

What have I learned from this
The learning never stops, knowing one workflow (rgb) only gets you part of the way, when you slide down a different path (sho, hoo, …). I’ve come across many tutorials and pixelMath combinations (foraxx, DreamsPlease, CrazyPanda - who comes up with these names 🙃). Given that the cloud cover is probably going to stick for some time, it’s going to be ‘cloudy nights = education time’ for a while 😂 … and a lot of reprocessing on older images
Constructive guidance is always welcome and appreciated, if it helps me improve my imaging routine and processing skills …

Clear Skies everybody! 🤩✨🔭

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