How to change screen saturation?

[Alberto González]

Hello all,

I just got a new laptop (Dell XPS 15) that I ordered with an optional RGB LED
display. This display has a high color gamut (around 98% of AdobeRGB color
space). The problem is that probably to show off this capability the
manufacturer set it by default to a very high saturation level. On Windows I
just went to Intel graphics control center and set the saturation to -20.
However, on Linux I've been unable to find any way of doing something similar.

Does anyone here know how this could be done? I know it sounds like a minor
problem, but it's actually very annoying in regular use, not to mention for
photo editing which is one of the reasons why I ordered this screen).

This laptop should have an NVIDIA discrete card too (apart form the one
integrated in the CPU -core i3- from Intel), and I guess that installing the
proprietary drivers for it I might get a control center where I might be able
to change the saturation, but it seems like an overkill solution, especially
when I don't want to use that card or any proprietary drivers.

I'm not at all sure this is actually a hardware/drivers problem, maybe it's
just a software one and KDE/GNOME could have something to control the
saturation, but I didn't find it there either (I tried in KDE's CC to turn all
3 color slides down hoping it would change the saturation, but it only makes
the screen darker).

Any hint much appreciated. Thanks!
Alberto.