Image Integration Question. Pixinsight

[PKay (Peter)]

Hi Brains Trust

I was wondering the best way of combining 2 different sessions (consecutive nights).
I have 2 folders both containing the registered lights.
I perform integration of each folder separately and I get 2 integration results.

I tried to integrate the 2 integration results and it wont let me...says I need a minimum of 3)

I tried to integrate both folders at the same time and it was a disaster.

Lost now :-(

[RickS (Rick)]

Hi Peter,

The usual way to do this is to register the subs from both nights against the same reference image and then integrate them all together. Not sure why this was a disaster for you but at a guess maybe you used different reference images for the two nights or you had a problem with the same file names clashing? You'll need to make sure that all the file names are unique.

You can combine separate master images though it won't give quite as good a result (rejection will work better if you have a larger stack). If you only have two masters, make copies of both of them so you have four files and ImageIntegration will stop complaining.

Cheers,
Rick.

Originally Posted by PKay

Hi Brains Trust

I was wondering the best way of combining 2 different sessions (consecutive nights).
I have 2 folders both containing the registered lights.
I perform integration of each folder separately and I get 2 integration results.

I tried to integrate the 2 integration results and it wont let me...says I need a minimum of 3)

I tried to integrate both folders at the same time and it was a disaster.

Lost now :-(

[PKay (Peter)]

Thanks Rick

Yes I did use 2 separate reference images.

This means I will have to do the batch processing again for both nights (since I cant remember which images I used for reference.

Will try both methods you suggested.

My poor computer has steam issuing from it.

[RickS (Rick)]

Peter,

Ideally, you'll pick a good quality sub for the reference with a small FWHM and low Eccentricity (= round stars). The SubframeSelector script is a good way to measure the subs and pick a reference.

Cheers,
Rick.

[sil (Steve)]

+1 to Rick's advice.

You can use the integration frame as a reference target too dont forget. So in your example take the integration file for set 1 and use that as reference to create the registered frames for set two and then you can integrate ALL the registered frames from both sets in one go. You can actually use ANY image as a reference target even something you find online, though this can mean scaling your data in the process (reducing accuracy of signal) but it can be handy if you have a poor quality set (out of focus, streaking, etc).

I tend to manually register a small set of frames to create a temporary integration frame with a more solid SNR and then use that file as my reference to register my whole set (usually hundreds of frames) and I find I get stronger registration that way with my noisy sets.