The basic rundown(s) are as follows. Every option seems to yield the same results. I’ve dealt with it somewhat on the final product by applying a selective burn (midtones, shadows ~10%) but would like a more optimal solution.
1) import image series using LOAD FILES INTO STACK or dragging/dropping the files as smart objects.
2) Apply a blend to each layer – LIGHTEN – which creates the screenshot without banding.
3) merge layers with snapshot (CRTL+ALT+SHIFT+E), “merge layers”, “flatten image”, “merge visible layers”, saving the image as a jpg or layerless tiff.
Images were shot on a Panasonic GH4 which is less than optimal for astrophotos but this doesn’t APPEAR to be an in-camera issue