Convert raw image without altering its appearence

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Babu
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Convert raw image without altering its appearence

Post by Babu »

I'm new to ImageMagick and was wondering how I could go about converting raw files without altering how I captured them. The sort of things I'm try to prevent are images that are purposely underexposed being brightened up or having their white balance shift to a warm yellow, black and whites being colorized, etc.
I'm processing a large volume of mixed images so sorting through them and applying specific flags to each sorted batch is not ideal.
Last edited by Babu on 2019-03-23T11:17:47-07:00, edited 1 time in total.
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fmw42
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Re: Convert raw image without altering its appearence

Post by fmw42 »

I have moved your post from the Consulting forum to the Users forum, since the consulting forum is for PAID consulting as it says under the link to the forum.

I am not an expert on raw format images. So perhaps one of the other uses may be able to help further.

____________________

Please, always provide your IM version and platform when asking questions, since syntax may differ.

Also provide your exact command line and your images, if possible.

See the top-most post in this forum "IMPORTANT: Please Read This FIRST Before Posting" at http://www.imagemagick.org/discourse-se ... f=1&t=9620

If using Imagemagick 7, then see http://imagemagick.org/script/porting.php#cli


For novices, see

http://www.imagemagick.org/discourse-se ... f=1&t=9620
http://www.imagemagick.org/script/comma ... essing.php
http://www.imagemagick.org/Usage/reference.html
http://www.imagemagick.org/Usage/
https://github.com/ImageMagick/usage-markdown
https://imagemagick.org/script/porting.php#cli
seoking
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Re: Convert raw image without altering its appearence

Post by seoking »

It's not really possible to do it losslessly, for a variety of reasons. Raw images pixel patterns don't map to your typical raster formats, for one; a raw images will usually have more green pixels than red or blue, and the grid arrangement isn't the same. Plus, raw images live in a much larger color space than your typical raster formats, and almost certainly larger than your monitor.

Plus, if you didn't get photos of reference patterns, or at least a basic gray, you'll have a tough time finding an objective reference point for your color adjust.

You can try using a tool like dcraw, though my preferred workflow for raw is to use darktable, though sometimes I'll use hugin. Bottom line, though, is you need to work with some HDR-capable tools while you figure out what settings work well for your photos.
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