I think this particular stack process is the winner, Debbie. Excellent. What was the optical configuration and mount use? I noticed the contour-gradient lines even in that German comet animation so apparently it's a tough artifact to eliminate. Debbie wrote:
I just posted my image of the Orion Nebula in the gallery. I aligned and stacked this image last night and then decided that I'd try a different stack called an Auto Quality Graded stack algorithm in my processing software. It is essentially a weighted average of the 34 frames. Each frame is given a grade quality. I played with the brightness, contrast, stretch functions and this is what I came up with. It is on page 3 of my album.
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