Initial Calibration/Stacking Pipeline (Best Practices)

[jerryyyyy]

I have been happy with using the BatchPreprocessingScript (BPP) until I discovered that it did not deal with hot pixels in its current evolution... at least I have gotten to the point that I can recogniize what a hot pixel is...   

Have been advised to do the following:

1.  Use ImageCalibration (IC) to calibrate the lights (RGBL separately) to produce _c files.  (4 steps)
2.  Run CosmeticCorrection (CC) to zap the hot pixels to produce _c_cc files (4 more steps). 
3.  Run StarAlignment (SA) to register the files and produce _c_cc_r files (1 step I hope if I run them all at once).
4.  Run ImageIntegration (II) to produce the master RGBL files (4 more steps). 

The question is whether or not you can shorten this marathon by using BPP at some point to short circuit the route and cut down the 13 steps....

Secondary question are there good settings in CC for zaping satelite trails? 

Third question II also seems to have Hot Pixel rejection; does this duplicate CC?

I have to say that just running BPP seems to give me results that are not much worse (if not better) that the 13 steps....

Thanks for any help!

[MortenBalling]

You could start by making a CC setting, and make an instance of it.

Then run BPP, applying CC to your lights.

Finally run II manually.

BPP does pretty a good job on calibration, but you normally get better results doing II manually afterwards.

Default setting in CC normally removes satellites.

CC removes hotpixels during calibration, whereas II with a sigma setting, removes cosmic rays etc. You could also use II for removing hot pixels, but then you have to use dithering on your mount. Otherwise the hotpixel stays in the same spot, making it look like a star to II.

[jerryyyyy]

You could start by making a CC setting, and make an instance of it.

Then run BPP, applying CC to your lights.

Finally run II manually.

BPP does pretty a good job on calibration, but you normally get better results doing II manually afterwards.

Default setting in CC normally removes satellites.

CC removes hotpixels during calibration, whereas II with a sigma setting, removes cosmic rays etc. You could also use II for removing hot pixels, but then you have to use dithering on your mount. Otherwise the hotpixel stays in the same spot, making it look like a star to II.

Very helpful.  I did not get the idea I could make an instance of the CC process and "call" it from within BPP.  That worked.  I do dither so I think it got all the hot pixels.. at least when I look at the high and low rejections seems like they are there along with a couple satellite traces. 

The cosmic rays look like a short trace/line? 

How do you know II gets better results than BPP... BPP seems a lot easier... like to know the work was worth the effort.

In any case, thanks for the help! 

[Geoff]

How do you know II gets better results than BPP... BPP seems a lot easier... like to know the work was worth the effort.

See here http://www.astrosurf.com/jordigallego/articles.html for a good article on fine tuning II, which is what you can't do with BPP.
(Image Integration Techniques about a third of the way down the page)
Geoff

[jerryyyyy]

Thanks, steep learning curve here.  Luckily the slides are translated into English....