@keesscherer, thank you for your explanation and suggestions 😉
Firstly.
" There needs to be a diagnostics step that tells the user what is wrong at this point. And there needs to be a
short, clear workflow with just the steps for calibration of DSLR images with flats taken at a different iso setting. "
I totally agree with you, i'll work on that in the manual, instruction videos and I will put warnings in APP in the calibration process, to directly help the user to get optimal calibration.
"My point is that the program has a built in indication next to the lights “B”, “F” but that indication has no meaning when you load all masters and lights. Furthermore there is no check done by APP for this so it just starts to stack."
This assumption is not correct, let me try to explain.
Everywhere in APP where frames are calibrated these checks are done thoroughly, see screenshot 1 for the calibration code of finding and applying the masters (bias, dark, flat, BPM) to a light.
In a previous post, you mention the flat calibration is not done, although the F mark is visible. This assumption is not correct as well. I can assure you that the flat calibration is done, but with a badly prepared master flat. If you put bad master frames into APP it will never automatically adjust it. Nor would pixinsight or nebulosity or any other program. There simply isn't any information present to detect if the master frame is badly prepared and neither is there information present to "know" how to magically correct this.
Therefor your suggestion to create built-in warnings in het calibration engine while preparing the master frames is a very good idea which I'll definitely try to implement.
Lastly,
"A suggestion from me that will save you a lot of headaches in the future is to (And this is as we say in the Netherlands “Cursing in Church”) Add the following checkmark/option: “Calibrate flats with same (ISO/Gain) bias as Lights”
I think that your suggestion is to make something that is fundamentally wrong. Let me try to explain:
If you have
light frames of iso1600 and
a masterbias of iso1600.
and flat frames of iso 200
And you would apply the iso1600 masterbias on the iso200 flats, the read noise patterns in your flats are going to be strongly overcorrected wih a factor of 8, which is clearly something you don't want to do.
(And I really think that you have been doing this consistently in your calibration routine in PI, for which PI didn't issue warnings to you 😉 or did it ?)
( the ADU count of a pixel with iso1600 is roughly 8 times the ADU count of that pixel with iso200 for the some number of electrons, e-, that were freed by the received photons that were captured by the pixel.)
You might think, why not use that factor 8 as a correction factor? Well this could only give robust and reliable results if all camera's behave perfectly linear with respect to change in iso or gain. This is hardly the case, so this correction will never give reliable, robust or optimal results. Therefor, I will not implement this since it is bad practice.
Other applications do let the user do this and this leads to a lot of photographers having sub optimal calibration results without them even knowing it, which really isn't my goal to achieve with APP.
calirbationCode