Hi Dave From what I can see changes from the darks slider are not being fully included in the flattened image. Now that I am aware of the the issue I have had success just compensating for it. This image is from a test series I did with a star tracker I have on loan. You are welcome to play around with it a bit. The process I was using was a levels adjustment; darks slider to the right, whites to the left & mid tones as needed. Just making the Milky Way stand out a bit. Then new layer from visible, then gaussian blur (18 pixels for this image) and set the new layer to soft light. Creates a glow effect. Here is a link to a version that has basic processing in Lightroom: Adobe Creative Cloud Joe
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