Author Topic: Debayering Process vs. Debayering Script  (Read 1402 times)

Offline rtemen

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Debayering Process vs. Debayering Script
« on: 2017 September 25 09:40:49 »
I am using my Canon T3i for my lights.
I am at the point in my workflow where I need to Debayering my files, but I do not know the difference between the Debayer Process and the Batch CMYG Debayer Script or which is the appropriate on to use at this point.

Thanks for any guidance.

Rich

Offline pfile

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Re: Debayering Process vs. Debayering Script
« Reply #1 on: 2017 September 25 13:37:15 »
CMYG is for some oddball cameras that have a totally different type of filter over the sensor. canon and nikon cameras have RGB filters.

the newest version of the Debayer process can run in batch mode to debayer a bunch of files at once, so the various Debayer scripts are no longer necessary.

rob

Offline rtemen

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Re: Debayering Process vs. Debayering Script
« Reply #2 on: 2017 September 25 15:45:23 »
Thank you.
I will use the process.

Rich

Offline eridanus57

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Re: Debayering Process vs. Debayering Script
« Reply #3 on: 2018 January 15 07:13:24 »
Excuse me for the entry, my inexperience in the forum makes me explain my problem perhaps in an inappropriate place.
I bought a QHY168C ColdMos camera with APS-C format, the images are with the Bayer matrix, to convert them to the correct MaxIm DL color, but I would like to know if I can convert them into PixInsight, and what would be the correct process. The mosaic model is GBRG. THX

Offline bulrichl

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Re: Debayering Process vs. Debayering Script
« Reply #4 on: 2018 January 15 08:32:53 »
Hi,

I bought a QHY168C ColdMos camera with APS-C format, the images are with the Bayer matrix, to convert them to the correct MaxIm DL color, but I would like to know if I can convert them into PixInsight, and what would be the correct process. The mosaic model is GBRG. THX

Use PROCESS|ColorSpaces|Debayer.

Parameters:
Bayer/mosaic pattern: ....
Demosaicing method: VNG
Add the monochrome Color Filter Array (CFA) files
Set the output directory

Execute 'Apply Global' (blue circle)

However, I am somewhat skeptical about the 'GBRG', I read that the pattern is RGGB for this camera. This might depend on the acquisition software and the right setting in FormatExplorer|FITS|Miscellaneous Options|Coordinate origin.

Be aware that the pattern is changed if you rotate or mirror the monochrome CFA image. E.g., if you mirror at a horizontal axis,

RG  turns to  GB
GB            RG


Also, you have to be careful if you crop a CFA image - an odd number at the top or at left side will alter the pattern.

Therefore, avoid to apply geometric operations on CFA images. Use always the same acquisition software (for light, bias, dark, flat frames). Take a daylight image with your camera in FITS format, import it to PixInsight and have a look whether the image is true-sided. If NOT: change the above mentioned setting in FormatExplorer|FITS.

Then you can try whether GBRG or RGGB will result in correct colors. Make sure to unlink the color channels in ScreenTransferFunction (STF) when you judge the colors.

Bernd


Offline eridanus57

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Re: Debayering Process vs. Debayering Script
« Reply #5 on: 2018 January 15 18:47:48 »
Thank you very much, Bernd, for your concise notes, which I will certainly have in mind. Right now I have just arrived from an astrophotography session, I will put your advice into practice. Best regards