The 'Grain Equalization' parameter lets the user reintroduce removed noise grain in a modified, uniform way, that is; appearing of equal magnitude across the image (rather than being highly dependent per-pixel signal strength, stretches and local enhancements as seen in the input image).
The 'Grain Equalization' feature an acknowledgement of the "two schools" of noise reduction prevalent in astrophotography; there are those who like smooth images with little to no noise grain visible, and there are those who find a tightly controlled, uniform measure of noise grain desirable for the purpose of creating visual interest and general aesthetics (much like noise grain is added for a "filmic" look in CGI). The noise signature of the deliberately left-in noise, is precisely shaped to be aesthetically pleasing for precisely this purpose.
Lastly, it should be noted that the 'Grain Equalization' feature only shapes and re-introduces noise in the luminance portion of the signal, but not in the chrominance (color) portion of the signal.
In StarTools, your signal is processed (read and written) in a time-fluid way, by means of an ever changing equation for every pixel.
Signal evolution Tracking data mining plays a very important role in StarTools and understanding it is key to achieving superior results with StarTools.
Open an image stack ("dataset"), fresh from a stacker.
Nevertheless the result can look quite pleasing when simply browsing past the image in a Facebook feed.
The motion is configurable both by you and the viewer in both X and Y axes.
You can convert everything you see to a format you find convenient. Give it a try!