Arch Linux

Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

LCD monitor's display is tinted blue, even with 24-bit color

My laptop doesn't appear to be suffering from any graphics problems, but there's something weird about the display... Everything is tinted towards the blue end of the spectrum. This is especially obvious with shades of gray, which look like shades of dull blue (e.g. MurrinaLoveGray looks like dark blue glass). When I was running Vista, the colors looked normal. I'm guessing this is a gamma correction thing, but there doesn't seem to be any hardware adjust for gamma. How would I configure X to fix this?

iBertus

Member

From: Greenville, NC

Registered: 2004-11-04

Posts: 2,228

Re: LCD monitor's display is tinted blue, even with 24-bit color

It sounds like a color "termperature" problem. If I set mine to "cool" colors then it has a blue hue. You can use xgamma to set custom gamma correction factors. Also, you can store the values in xorg.conf with the Gamma option. You should consult the man page for xorg.conf.

Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

Re: LCD monitor's display is tinted blue, even with 24-bit color

Hmmm.

[proteus@caleuche ~]$ xgamma
-> Red  1.000, Green  1.000, Blue  1.000

Maybe this does not have to do with gamma correction...

Last edited by Gullible Jones (2007-06-03 21:37:42)

pauldonnelly

Member

Registered: 2006-06-19

Posts: 776

Re: LCD monitor's display is tinted blue, even with 24-bit color

Hmmm.

[proteus@caleuche ~]$ xgamma
-> Red  1.000, Green  1.000, Blue  1.000

Maybe this does not have to do with gamma correction...

That just means you're using the default gamma settings. If they're wrong, they're wrong. I found that Red  1.200, Green  1.000, Blue  0.550 comes out right on my monitor. I'm surprised that Vista didn't exhibit the same problem, but maybe it came pre-corrected.

Last edited by pauldonnelly (2007-06-05 00:44:05)

Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

Re: LCD monitor's display is tinted blue, even with 24-bit color

Hmm. Is there any list of monitors and optimal gamma corrections somewhere out there? Some way of finding the optimal gamma settings for a given monitor? 0.8, 0.8, 0.6 looks okay, but it's still kind of off, browns looking pink and stuff.

(Weird, the screen looks kind of washed out no matter what I put into xgamma and regardless of the brightness. I wonder if this has any relation to the xf86-video-unichrome brightness bug.)

Last edited by Gullible Jones (2007-06-05 03:02:13)

pauldonnelly

Member

Registered: 2006-06-19

Posts: 776

Re: LCD monitor's display is tinted blue, even with 24-bit color

You might swing by http://www.normankoren.com/makingfineprints1A.html for information on configuring it. I don't know of any list, but there might be one somewhere.

Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

Re: LCD monitor's display is tinted blue, even with 24-bit color

Okay, I tried QuickGamama (under Wine), and it gave me this:

Sorry, QuickGamma cannot be used on your computer.

Your graphics card does not support a loadable color lookup table.

Is this an actual issue or does QuickGamma just not like being used with Wine? Because my i950 video hardware may not be very powerful, but it is definitely not ancient.

(Also tried using a program called xcalib, but apparently it needs to have an ICC profile. Is there a way to find the one for my LCD screen, which is some unspecified and probably very obscure brand? Is this one of those things that's contained in the firmware or whatnot?)

Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

Re: LCD monitor's display is tinted blue, even with 24-bit color

Okay, just to see if this was unique to Arch in some way I installed Ubuntu on my third partition. Still there on Ubuntu.

(And apparently the video hardware is 945GM, not 950.)

Last edited by Gullible Jones (2007-06-11 20:04:43)

pauldonnelly

Member

Registered: 2006-06-19

Posts: 776

Re: LCD monitor's display is tinted blue, even with 24-bit color

Sorry, you've lost me. I was suggesting that you experiment with various arguments to xgamma using the test graphics at that site.

Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

Re: LCD monitor's display is tinted blue, even with 24-bit color

Oh... Sorry.

(Those test graphics aren't especially useful to me, at least the ones I saw, as I'm aiming for something equivalent to gamma 1.0.)

George_K

Member

From: Russie, Saint-Pétersbourg

Registered: 2006-09-27

Posts: 75

Re: LCD monitor's display is tinted blue, even with 24-bit color

Maybe your display is supported by ddccontrol.

Gullible Jones

Member

Registered: 2004-12-29

Posts: 4,863

Re: LCD monitor's display is tinted blue, even with 24-bit color

Nope, apparently it doesn't support DDC or CI.

Last edited by Gullible Jones (2007-06-12 18:49:31)