[RCC] Please critique my Gecko

The diffraction spikes do not look right, especially the small ones, probably from the stretch but could also be from star reduction in BXT. Try removing the stars before stretching. I think the noise reduction is OK as is although could maybe use some tweaking.

thanks, so I should create my starless image, and then simply stretch on that, and then add back the stars. So BlurX should be done on starless image?

There are several approaches to processing the image, and mine is to use SPCC to get the best color possible based on your sensor and filters. If necessary I do DBE and then as Tim suggested use PSFImage or DynamicPSF on the unstretched image with stars and use BXT on a small preview to inspect what the stars and details look like before applying the full BXT.

I then stretch very carefully in small steps and separate stars for processing nebulosity and stars separately on the RGB. I do not use GHS alone but combine it with other stretches and iterate in small steps, ArcSignStretch helps intensify color but has to be used sparingly in combination with HT and GHS or AutoHistogram.

Once I am happy with the color I create a separate Lum either by extracting Lum from the RGB or combining the channels to bring out best detail, and work on sharpening that using PS or PI tools and use LRGBCombination when I am ready to combine.  All this is done starless.

I finally get the stars balanced with the nebula and this is a trial and error process too and combine and do some final cleanup.