
A Hands-On Guide to Color Correction - rhayabusa
https://www.planet.com/pulse/color-correction/
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pluteoid
...for this particular satellite imagery. It's a rather limited overview of
color correction in general.

> On top of this, what we see with our eyes is very different from the raw
> data captured by a scientific instrument or digital camera.

Yes, this is why photographers who avoid postprocessing because they're
"purists" who like "unenhanced, natural images" sometimes deliver unnaturally
bland images. The visual system phenomena at play are high dynamic range,
simultaneous contrast, chromatic adaptation, and perceptual uniformity.
Correcting for these things effectively often requires a separate treatment of
each (but software lets you do that quickly). The article shows a rather crude
approach – there are techniques available that give better results in the same
time.

See for example Dan Margulis's well-regarded "Modern Photoshop Color
Workflow".

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vvanders
Yup, I'm also a huge fan of "Photoshop LAB Color: The Canyon Conundrum and
Other Adventures in the Most Powerful Colorspace" by the same author. For
photos LAB colorspace provides a great way to get images closer to how we
actually perceive them.

~~~
clumsysmurf
Margulis updated that book (2e) recently: [http://www.amazon.com/Photoshop-
LAB-Color-Adventures-Colorsp...](http://www.amazon.com/Photoshop-LAB-Color-
Adventures-Colorspace/dp/0134176103)

i also found this pretty good too [http://www.amazon.com/Color-Management-
Quality-Output-Workin...](http://www.amazon.com/Color-Management-Quality-
Output-Working/dp/0240821114)

Too bad focal press Kindle books are just as expensive as the softcovers, and
are usually done quite poorly.

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StavrosK
Alright, this is theoretical (as in, I've never done it), but you can use
adjustment layers to perform what the article describes non-destructively
(i.e. leaving the original image untouched). Then, you can stick an image of
the entire color space where the background image was, and you'll basically
get:

result = adjustments(color_space_image)

Which is a color LUT and can translate every color in the original image to
the new color. Photoshop can load LUTs directly (I'm just not sure how to
create them), and you can incorporate them into your own programs by just
looking up the pixel in the original color space and the adjusted one.

This has been a content-free comment by your friendly rambler.

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brudgers
Non-destructive editors include Adobe Lighttable and the open source
Darktable.

Darktable: [http://www.darktable.org/](http://www.darktable.org/)

~~~
StavrosK
Adobe Lightroom, you mean. I have used Darktable and would recommend it, it is
a great piece of software.

~~~
brudgers
Yes, that's what I meant and was trying to be polite by mentioning it on my
way to Darktable.

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theoh
For moviemaking, the analogous process ("color grading") is starting to be
done live at the time the shots are recorded, on a digital screen connected
(in some cases wirelessly) to the camera. The color grading parameters are
stored as metadata attached to the digital video files and can then be applied
and/or tweaked later in an editing suite.

[http://blog.abelcine.com/2015/07/09/live-color-grading-
with-...](http://blog.abelcine.com/2015/07/09/live-color-grading-with-the-
varicam-part-1-camera-setup/)

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kelsolaar
I was expecting quite a lot more, this is simple, too much actually. I would
have liked to see more on topics such as histograms, how to read them, work
with them, mention of subjects such as lift-gamma-gain (or GOG), reference to
high-end grading systems, vectorscopes, RGB parade, etc...

An excellent resource on (high end) colour correction / grading is this book
by Alexis Van Hurkman:
[http://vanhurkman.com/wordpress/?p=2854](http://vanhurkman.com/wordpress/?p=2854)

