One more batch preprocessing question

[Diane Miller]

Ran BPP on a couple of sets of the Milky Way core (from two different nights with slightly different conditions).  Same camera, settings and lens.  Had what looked like good flats, biases and darks for both runs.  For both I got very subdued grayish-cyan images when I did the screen stretch on the integrated lights.  Then last night I shot the Rho Ophichui region, very similar sky conditions to the second of the core region shots, with slight LP and some haze.  Same camera, lens, settings.  Same processing as far as I can tell.  But the integrated light came out very orange after the stretch.

The files are here:
https://dianemiller.smugmug.com/Photography/Files-for-PI-forum/n-FPknxD/i-jJLSsv6

Will go back to digging thru study material, but can somebody give a quick opinion: Am I doing something wrong on either the subdued or the very orange results?

Many thanks!

[msmythers]

It looks like you have STF linked. Here is one of my images with the same issue. The top is STF linked and the bottom is unlinked. This is not a problem as you haven't done any background neutralization or color calibration at this stage.



Mike

[Diane Miller]

Linking or unlinking STF is something I don't know about.  In both cases (orange and gray images) I just clicked the far right button on the top bar to see if I had anything.

Back to the books (and I wish there was one) -- thanks!  I'll get back to Jim Morse's cribsheet and the Keller videos and see how far I can get.

[msmythers]

Here is a short video(no audio) using STF(ScreenTransferFunction tool). https://drive.google.com/file/d/0B13r3kYqTf8NXzFrWWEtaVk4RlE/view?usp=sharing If the video seems blurry just pause and restart the video.

This is the official documentation on STF.   https://pixinsight.com/doc/tools/ScreenTransferFunction/ScreenTransferFunction.html  Some buttons look different but they are the same. This document is many years old.

You might see in some tutorials the use of the STF buttons on the top toolbar. I've included a screen shot of those buttons.


Mike

[Diane Miller]

Thanks Mike -- I had not noticed the little "explanations" of the STF icons.  Wonder if I have them turned off...  They will go into my notes.  If I ever get through this process I might have a PI for Dummies book before Warren finishes his real one.  Will check your sources.