If you're referring to the blue color grading, the easiest way is to play
with white balance and stuff that modifies the luma channel. Another
fancier alternative is the low light module:
http://www.darktable.org/usermanual/ch03s04s05.html.php#low_light
On Mon, Dec 18, 2017 at 12:22 PM Germano
How would you use darktable in order to get colour correction like in
Mr. Robot TV series?
Example https://twitter.com/bestofmrrobot/status/942213386749775873
in particular, the second image
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