Question about Star Alignment in Pixinsight - Forums

Topic starter

Frequent contributor

Jan 21, 2023

Tonight everything was going great until my headlamp batteries died and it was very dark while I was checking a cable. I bumped a tripod leg. So I polar aligned again and went to my target to continue shooting, but I noticed that the position of the new images after I polar aligned the 2nd time were not exactly in the same position as the images taken before I bumped the tripod leg,

Is this going to produce a headache for me when I try to register and align the images? Which settings in "Star Alignment" should I pay attention to?

Thank you!

Jerry

Engaging

Pistachio_Enjoyer

Jan 21, 2023

Depends on how far off your later images are. When star aligning, you select a reference image and all other images are aligned based off of that. You might see your other images get clipped somewhat.

Steve Spring

Jan 21, 2023

Hi Jerry,

So long as a fair proportion of your stars remain in the field of view then star alignment will probably handle it for you.

As @Pistachio_Enjoyer has said, choose your ref frame and run it. The results will explain everything.

Do you use dithering between shots?

If not you may have inadvertantly done your first dither, albeit by an uncalculated distance

Supportive

Monty Chandler

Jan 21, 2023

Should be fine. Set RANSAC tolerance to 3 or 4 and iterations to 3000. Cheers

Jerry Gerber

Topic starter

Frequent contributor

Jan 21, 2023 · Edited: Jan 22, 2023

Great, thanks Monty, Steve and Pistachio Enjoyer! The 113 subs all registered successfully. Thank goodness for computers. I thought that registration would only work if the stars were a few pixels off, but it's surprisingly far more tolerant than I thought.

Well Written Respectful