WBPP: How to Combine with Different Flats?

[mlamb1]

With WBPP, how do I combine with groups from different nights (big difference, in interim optical train was broken down and replaced) that have different flats?

I try to keep my optical train together to use the same master flats for several weeks, but recently I went from my Esprit 100 on M33 to a camera lens for broad target, M31.  When processing, I decided that my M33 Ha needed more data, as the HaRGB background was blotchy.  So I reassembled the Esprit 100 train for several extra hours of Ha.  The camera orientation is slightly different, so my new night's flat orientation is not the same as my old.

Can WBPP be run in a way to apply different flats for the 2 subsets, and subsequently combine the two?

Also, I am using a ASI183mm-Pro and my flats are of short duration (max of 1.3s for Ha), so I do NOT use Flat Darks, using Bias only.  I did NOT check "Calibrate with flat darks only" and I get a warning about it using my 240s Darks. 
Am I correct?  How do I get WBPP to use Bias instead of Flat Darks?

I am a newbie and have only been using PI for 3 months.

[dhickey]

For calibrating the Flats with Bias instead of Flat Darks, you actually want to check the "Calibrate with Flat Darks" box.  If Darks of the right duration are not found then it will use the Bias.  At least that's what it did about an hour ago when I was experimenting with WBPP - you'll see a Warning message when you run or perform the diagnostics indicating such.

For multiple nights where you need to use different flats you will need to run WBPP separately for each night.  If you want to see integrated output for each night to check your progress, you can let it go through the registration and integration phases as well.  If you don't care, tell it to Calibrate Only.  Once each night has been individually calibrated you will need to pick a reference frame and then register all of your calibrated files to that reference.  I don't think you can do that with WBPP, you'll need to use the StarAlignment process.  At that point all of your calibrated files will be registered to the same reference frame and you can do ImageIntegration.  (if you use LocalNormalization you'd run that against the newly registered files before ImageIntegration of course)

I haven't seen any way to do it all in WBPP across multiple nights when you need to use different flats to calibrate each night.  If someone does know a way, I'm sure they will jump in.

Dave

[mpendleton]

Is the only solution to run WBPP for each batch of flat frames? Despite my initial excitement over the script it seems the script has very little usefulness, at least in a world of having different sets of flats for different dates / pier flips, etc. Am I missing something?

[dhickey]

Is the only solution to run WBPP for each batch of flat frames? Despite my initial excitement over the script it seems the script has very little usefulness, at least in a world of having different sets of flats for different dates / pier flips, etc. Am I missing something?

I believe that is the case.  The author has a good write-up of the script (https://www.tommasorubechi.it/2019/11/15/the-new-weighted-batchpreprocessing) and multi-night integration with different flats is not mentioned.  There would need to be some way to associate a set of flats with a corresponding set of lights that does not exist (that I see) in BPP or WBPP.

[mpendleton]

Is the only solution to run WBPP for each batch of flat frames? Despite my initial excitement over the script it seems the script has very little usefulness, at least in a world of having different sets of flats for different dates / pier flips, etc. Am I missing something?

I believe that is the case.  The author has a good write-up of the script (https://www.tommasorubechi.it/2019/11/15/the-new-weighted-batchpreprocessing) and multi-night integration with different flats is not mentioned.  There would need to be some way to associate a set of flats with a corresponding set of lights that does not exist (that I see) in BPP or WBPP.

BPP has the Add Custom setting which works fine for manually defining the association between flats and lights. WBPP has the same command but for some reason wants to integrate all the custom groups as separate masters rather than integrating a filter color. Even with Calibrate Only the errors appear, making it impossible to even calibrate. Seems just getting rid of that error could be an answer.