Last January (and February) of this year was a remarkable time. PixInsight had just released its new CometAlignment process which coincided with the prominence of C/2022 E3 (ZTF). In addition new "powers" were bestowed upon StarXTerminator (I advocated strongly for them... ). Taken together entirely novel ways of approaching comet image processing are now possible that minimize the issues that have always been the bane of the enterprise.

I went a little crazy and created demonstrations for just about every variation in my Horizons collection of comet videos (examples for mono processing, OSC, implications of CFA drizzling...and more!). More recently I have proposed another innovation that improves the S/N of the comet by acquiring comet *tracked* data and still processed to produce a comet against a starfield (or even scene!) as expected. 

However, this image is derived from data taken on January 26th of 2023. I had not gotten around to processing it since I worked on other examples from other nights during this same week. So this data was processed with the latest methods (for star-tracked data) using CometAlignment and SXT. There are a handful of useful improvements for processing in PixInsight. One in particular is the use of LocalNormalization that is configured specifically for comet data. 

All of this being said, the limiting factor for the ultimate quality of the image are the star residuals (in this case in the form of star residuals from their halos). These residuals are faint compared to what was the norm prior to star removal tools- as statistical rejection simply cannot achieve similar results. However, this area will continue to improve and consolidate these workflows as robust. 

I have created a video that shows all of the steps I took. 
Featured in this video is the beta version of a soon to be released script called "ImageBlend" by Mike Cranfield. I asked Mike to create this because I think it can be a powerful tool to make blending of images easier in PixInsight.  There are other scripts that kind of do a similar thing- but not really. ImageBlend allows for the blending of two images using the standard set of blend operations, with a real-time preview, AND (most importantly) includes the histogram adjustments for full control. Members of AdamBlockStudios.com are always at the forefront of possibility.

-adam

P.S. I will be publishing these comet videos tonight... perhaps in time for Christmas. lol