Bad solution with stacking two photo session?!


Feb 17, 2020
Hello there (o:

I have do two photo sessions form M101. I done the images in two nights but with the same settings (810 second and ISO 800).
I stacked with WBPP both photo session esparat. See the both pic on the top in the attached picture.
Now I puted this tow pic session together over the processes "StarAligment" and "Imageintegration". I use "Linera fit clipping" (see pic below right) and "Winsored sigma clipping" (see pic below left).
The relution is very bad. ))o:
What is my mistake?

I hope some one can help me.




Well-known member
Feb 1, 2014
No one has answered this... because I think the question might be confusing.

I do not understand what the top images are. You say you stacked them in WBPP... but this means the top images are combined and also had StarAlignment and ImageIntegration used. Otherwise we are looking at a single raw image.

You seem to be saying that in the top images you did not use Rejection in image integration and the bottom images you did.
But the bottom images do not look calibrated. It does not look like flat fields were applied. This is not caused by StarAlignment or ImageRejection.
It just looks like you combined raw or uncalibrated frames.

It think you might need to make more screenshots to explain what you did and what the problem is.
I really tried to think about what you are showing for a while... and I can't quite figure it out.



Apr 19, 2020
Hi Andreas,

to me it sounds like you are integrating two already integrated images from 2 sessions. I never did this, therefore I do not know if this would result in what you show (the 2 lower images).
When you want to combine data of 2 sessions you should calibrate the images of the 2 sessions individually but then run star alignment and image integration on all images of both sessions together.

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Feb 17, 2020
Hello Adam and David,

First of all thanks for your answer!!!

it is difficult to explain everything in English, but I will try again.

Here is my approach again:

1. I stack each photo series individually with WBPP. That I get the two stacked pictures above (see attached picture). I do this to see if everything "worked" and it looks good!

2. With the WBPP, the debayered images are generated from the individual lights (RAW FILES) (for both photo series SINGLE !!!), these (debayer images generated from BOTH photo series) are then overlaid with "StarAligment". So now I have from the BOTH photo series exactly overlaid images Lights.

3. I now integrate these images (debayered lights from BOTH photo series) with "image integration" into one image (master light). I used "Linera Fit Clipping" (see picture below right) and "Winsored Sigma Clipping" (see picture below left).


But the result (see the two pictures below) is much worse than the two pictures generated from WBPP (seen in the picture above). Why?

What am I doing wrong?

I hope you have a solution.