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All my CR2 conversions are yellowed

Posted: 2019-09-24T05:01:56-07:00
by doncaruana
When I convert CR2 to JPG, I end up getting this yellowing effect. This is just a plain conversion, nothing fancy at all and I'm using 7.0.8-66 Q16 x64 on Windows 10. What can I do to get rid of this effect (or where is it coming from?)

Original:
Image

Conversion:
Image

Re: All my CR2 conversions are yellowed

Posted: 2019-09-24T05:41:39-07:00
by snibgo
I suspect a colour-balance problem.

You don't say what command you used, or what delegate your version of IM is using to process the raw file. If you browse this problem in these forums, you will find my general advice: use a program such as dcraw directly to process raw files.

Re: All my CR2 conversions are yellowed

Posted: 2019-09-24T05:47:35-07:00
by doncaruana
I just used magick <source.cr2> <target.jpg> after an install, so everything "out of the box". I did see some stuff about dcraw but wasn't able to figure out how to use it for this yet. I'll see if I can find some instructions I can follow (unless you have a handy reference! :) ).

Thanks

Re: All my CR2 conversions are yellowed

Posted: 2019-09-24T06:04:33-07:00
by doncaruana
Well...I tried just a plain run of dcraw...dcraw -v -W -O <target.jpg> <source.cr2>
The output wasn't readable by windows. But then I did a convert/resize of that using imagemagick to a new jpg and that one has the same issue.

Re: All my CR2 conversions are yellowed

Posted: 2019-09-24T06:18:51-07:00
by snibgo
dcraw can write PGM or TIFF format only. It can't create JPG files.

dcraw (and other raw processors) have many controls. IM doesn't provide simple access to those controls. For basic conversion to sRGB I suggest:

Code: Select all

dcraw -6 -T -w -O out.tiff in.CR2
This makes a TIFF file, which IM can then convert to JPG.

Re: All my CR2 conversions are yellowed

Posted: 2019-09-24T08:09:32-07:00
by doncaruana
snibgo wrote: 2019-09-24T06:18:51-07:00 dcraw can write PGM or TIFF format only. It can't create JPG files.

dcraw (and other raw processors) have many controls. IM doesn't provide simple access to those controls. For basic conversion to sRGB I suggest:

Code: Select all

dcraw -6 -T -w -O out.tiff in.CR2
This makes a TIFF file, which IM can then convert to JPG.
Coming back to check after I went off and worked at this for a while and that ended up being exactly what I used! :) Ended up looking pretty darned close to the original too. Thanks

Re: All my CR2 conversions are yellowed

Posted: 2019-09-24T08:30:49-07:00
by snibgo
Glad that helps. But note that this isn't "close to the original" because there is no original. There are only different renderings of the raw (mosaiced) image, which might include a JPEG rendering made by the camera or by other software.