issues with registration with large number of frames and slow drift

Software Siril
#1

Hello,

I am bug a beginner and I have a DYI mount which is not yet very good.

Yesterday, I tried to image ngc457, I have around 400 frames, but I have a slow drift of around ~0.4 pixel per frame. This means, after 200 frames that I have a 80 pixel drift.

The issue is that, siril seems to have no issue finding the proper star for the first 200 to 250 frames or so, but then, it seems to get confused and the registration seem to pick the “wrong” star, and my frames become badly aligned…

I am doing a 1 star alignement. When I try 2 stars, it drops (fails) on around 50% of my frames…

What can I do to fix this?

  • Should I split my frames into 2 stacks?
  • Is there a way to tell Siril that to “follow” a star during alignement?
  • Would changing the reference frame help?

Thanks,
Cyrille

#2

Hello.

No.

Why don’t you use the global registration? This algorithme is done for that. With the 1star you can only handle translations.

Yes it is possible. Everything is explained in the documentation.

Sure it could, by chosing an image in the “center” of the drift.

But again, the global registration would probably give you best results.