Master calibration files

[cdesselles]

Being a relative newbie, I have a very basic question.  How do I create master darks, flats, and bias files?  The Batch Preprocessing Script appears to require lights as part of its process.  But I would like to construct a master bias library at the minimum that I could save for use in calibrating many images in the future.
So how do you gentlemen do it?

[Geoff]

Just go ahead with bias, darks and flats loaded without loading any light frames. You will get a "warning: no light frames". Just ignore it: it's only a warning in case you forgot something. Just hit "Continue" and your masters will be generated.
Geoff

[sreilly]

And see http://www.pixinsight.com/tutorials/master-frames/index.html for the old fashion way. This also gives a pretty through explanation about the process.

[cdesselles]

Thanks!  So simple it was scaring me off.  I thought there had to be more to it than that.

One more question.  Since I shoot with a Canon DSLR, must I de-Bayer and convert to FITS first?  Or just let Batch Preprocessing do it all? 

[pfile]

BPP will do it for you as long as you have "CFA Images" checked.

i think a lot of DSLR users get tripped up by this because of the jargon surrounding color cameras - "DSLR", "OSC" (One-Shot Color), "CFA" (Color Filter Array), Bayer, etc. it's probably not obvious to a DSLR user that a DSLR is an OSC or that the DSLR files are in mono CFA format until they have been debayered into 3-plane color images. and of course there's a CFA representation which is 3-plane but still Bayered data.

rob

[cdesselles]

Thanks again.  But if I wanted to do it the old-fashioned way, not with the BPP script but with separate applications of Star Alignment, Image Calibration, and Image Integration shouldn't this Raw files be de-bayered and saved as FITs first? 

To simplify: What are the proper steps to take (in order) to calibrate, align, and stack DSLR images without using Batch Preprocess? 

[pfile]

oh, in that case:

calibration -> debayering -> staralignment -> imageintegration

rob

[cdesselles]

Thanks again.  But can I do this with .CR2 Raw files or must I convert them to FITS first?

[pfile]

you don't have to convert the CR2 - ImageCalibration will read a CR2 just fine, and write out a FITS file.

just make sure to put the right format hints into ImageCalibration. normally you want "raw cfa" which will cause ImageCalibration to read in the CR2 as a raw file with no black point correction, and represent it as a mono (single-plane) image.

once you have all the calibrated fits files, you can use the BatchDebayer script to debayer the files, then load the debayered files into StarAlignment, and finally load the aligned files into ImageIntegration.

rob

[cdesselles]

Once again, thanks.  I think I have it all in order now.  (I love this forum!)