The Monkey Head, along with the nearby Jellyfish, make the last of the grand nebulae before galaxy season takes full control of the northern sky.  As such I wanted to do this justice and took my time with it.   I like how a traditional pure SHO mix gave the most nuanced view of the structure, but the SII was weak and needed a lot of time to lower noise levels.  All attempts at suplimenting the SII with some Ha really took away from the differentiation of the more subtle structures.  Interestingly, that was the case with the color mix but the luminance channel was fine with just Ha and OIII.  I mixed 33% OIII with 67% Ha for the Luminance channel.

The powerful star at the center, HD 42088, is 30 times the mass of the Sun and is responsible for what we see.  Its high energy winds are pushing the nearby gasses away and, where the gasses are densest, forming pillars.  When you consider this the nebula begins to appear as a globe to my eye.

17 ten minute Ha subs was enough.  But it took 37 OIII and 60 SII subs to get those channels up to snuff.  The stars are RGB and 12 two minutes subs for each channel were used.

Calibration and stacking were done in Pixinsight.  I combined the SHO and RGB channels in PI and did color calibration there as well.  The PseudoLuminance was also created in PI.  Stretching started with a Masked stretch and then a further stretch with Histogram transformation.  From there I worked in Photoshop.

My QHY600M suffers from horizontal banding with weak narrowband data.  Even 60 subs was not enough to eliminate it from the SII.  I use a debanding tool in the old TOPAZ denoise 6.0 - the pre-AI tool that I'm not sure if they sell any more.  That works great on this banding.  I also de-noised the color with that tool.  De-noise on the PsuedoLuminance was done with Adobe Camera Raw.  This isn't the most sophisticated tool but it doesn't produce artifacts and it's easy to focus the effect on the dimmer areas by using a Luminance mask.

Sharpening we done subtly with and Unsharp Mask at two scales.  One about about 8 pixels (just above my FWHM) and one at about 70 pixels.  Stars and background were masked for the sharpening.  

SHO color was adjusted with about every color tool Adobe offers.  I try to work very incrementally to move the greens and yellows toward the red for a more natural look - if that makes any sense with Narrowband...  I particularly like using the LAB space, adjusting the color contrast with curves.  Adobe camera raw also gives nice tools for shifting specific colors in the direction you want.  The Channel Mixer tool is also very powerful, allowing me to move a part of the green to red.  

I used StarXterminator to create a star mask.  This was used for many things, one of which was dropping in the RGB star data as a Hue blending layer.  

Thanks for reading this far!