I previously posted on using astronomical software to “stack” nightscape images, providing improved quality of long-exposure images. I recently began using some astronomical image processing software to improve the appearance of stars, the milky way, and other sky features. There are many software options available for this purpose. I selected the free IRIS program (Windows) based on some excellent photos that were processed using that software. As a Mac/Linux user, I was pleased to see that IRIS runs perfectly under Wine, so I can use it conveniently on any of my computers (I have several). Like most astro software, IRIS is not designed for novices, but there is very extensive documentation and tutorials on the software web site. Here are a few processing examples:
These images give some indication of what can be done to enhance images in IRIS. The selective Gaussian blur operation increases the apparent size of brighter features, so that they are easier to notice and recognize. The color-stretch command exaggerates the colors so that the faintly colored stars stand out more vividly.
I will inevitably become interested in having a more refined control over my image processing. In the future I will probably shift my attention toward image processing in Python, so that I can build them into my computer-controlled field imaging setup. Apparently Python is currently unpopular among amateurs, and it may take some effort to stitch together a working collection of amateur-grade tools, but it is encouraging that at least a few others are working in that direction.