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[Closed] Original RAW image

Posted: Wed Jan 09, 2019 5:37 pm
by Leraillez
Hi,

I can' find the way to show the original RAW image, the one that does not apply the user's choice of lighting on the camera like Tungsten, Sunny... I would like to see the "Auto" white balance of the camera, the one with no color modification.

Is this possible?


TIA,

Re: Original RAW image

Posted: Thu Jan 10, 2019 8:52 am
by forum_adm
RAW files are not stored as normal RGB files. They use the bayer grid or other encodings.

So, the files have to be developed for display.

You can adjust the library in the prefs.

dcraw supports some options:
Screen Shot 2019-01-10 at 08.50.23.jpg
Screen Shot 2019-01-10 at 08.50.23.jpg (174.75 KiB) Viewed 3962 times

Re: Original RAW image

Posted: Thu Jan 10, 2019 4:38 pm
by Leraillez
RAW files are not stored as normal RGB files. They use the bayer grid or other encodings.

So, the files have to be developed for display.
Yes, but the Raw file in itself does not take into account the user's selection (auto, sunny, tungsten...) but when shown "as is" the user's selection is applied to the original data and displayed on screen. In the EXIF data you find the user's choice (sorry French version of GC.

Lightsource: Tungsten (Incandescent) or another
Or
Lightsource: <unknown> if the camera was on "Auto" mode concerning light.
And farther down you will find a list of color corrections:

---- SR2SubIFD ----
(BB=WB, RVVB=RGGB)
WB RGGB Levels Auto: 2660 1024 1024 1272
Niveaux BB RVVB: 1428 1024 1024 2688
Color Matrix: 1406 -391 9 -42 1356 -290 22 -53 1055
Niveaux BB RVB daylight: 2316 1024 1516
Niveaux BB RVB Clouds: 2504 1024 1392
Niveaux BB RVB Tungsten: 1428 1024 2688
...

The first lines are there to correct the "quality" of the Bayer filters and are those applied if you choose the "Auto" mode on the camera. Auto mode on the camera is named Light Source : <unknown> in the EXIF

When I use LR and choose "Auto" instead of "As is", the same image is displayed whatever light source I have chosen on the camera. This is why I believe that the RAW image data does not take into account the user's light source selection. And we can therefore change this after on the computer.

N.B. I use a Sony A7ii and I don't know if all camera manufacturers give the same information in the EXIF part of the file.

Re: Original RAW image

Posted: Thu Jan 10, 2019 5:25 pm
by forum_adm
Just use the draw import without checked corrections in this case.

Re: Original RAW image

Posted: Thu Jan 10, 2019 6:35 pm
by Leraillez
Thanks very much


Benoît Leraillez