Wide Gamut Monitors (Cautionary Note)

[Visuals]

Hi all

Here's something which you may want to take note of, it's about wide-gamut monitors.

Extracted from Karl Lang's opinion..

Click here for original full writing: http://luminous-landscape.com/forum/index.php?showtopic=9613&st=0&p=54301&#entry54301

1) A wide gamut LCD display is not a good thing for most (95%) of high
end users. The data that leaves your graphic card and travels over the
DVI cable is 8 bit per component. You can't change this. The OS, ICC
CMMs, the graphic card, the DVI spec, and Photoshop will all have to be
upgraded before this will change and that's going to take a while. What
does this mean to you? It means that when you send RGB data to a wide
gamut display the colorimetric distance between any two colors is much
larger. As an example, lets say you have two adjacent color patches one
is 230,240,200 and the patch next to it is 230,241,200. On a standard
LCD or CRT those two colors may be around .8 Delta E apart. On an Adobe
RGB display those colors might be 2 Delta E apart on an ECI RGB display
this could be as high as 4 delta E.

It's very nice to be able to display all kinds of saturated colors you
may never use in your photographs, however if the smallest visible
adjustment you can make to a skin tone is 4 delta E you will become
very frustrated very quickly.

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Are the Dell 2408 FPW and Samsung 245T considered wide-gamut LCDs? I'm concerned whether using these mid range Adobe Color Space displays may result in a 'greater colorimetric distance' or 'higher Delta E'. If it does, then it is probably worse off than sticking to an ordinary sRGB display. :sweat:

Does anyone know?

 

[lennyl]

Are the Dell 2408 FPW and Samsung 245T considered wide-gamut LCDs? I'm concerned whether using these mid range Adobe Color Space displays may result in a 'greater colorimetric distance' or 'higher Delta E'. If it does, then it is probably worse off than sticking to an ordinary sRGB display. :sweat:

I'm far from an expert in color management, but I was under the impression that Karl Lang was referring to monitors with more than 8 bits per channel? Those monitors are priced somewhere in the stratosphere, unlike the Dell 2480WFP-HC and Samsumg 245T.

Take for example the HP LP2480xz, an "affordable" 24 inch, 1920x1200, 30 bit display. Affordable to HP board members, maybe. Original price US$3499. Now available with a huge US$1000 discount, only US$2499. (btw "affordable" is in HP's press release, not my word).

http://www.hp.com/hpinfo/newsroom/press/2008/080610xd.html

http://h10010.www1.hp.com/wwpc/us/en/sm/WF05a/382087-382087-64283-72270-444767-3648397.html

You should be able to get more accurate colors after calibration with something like the 2408WFP-HC.

 

[theRBK]

I'm far from an expert in color management, but I was under the impression that Karl Lang was referring to monitors with more than 8 bits per channel?

not really... bit depth is not a measure of gamut, or the range of colour that can be displayed, which is what Karl Lang is talking about... bit depth is how finely the colour may be differentiated... I'm sure there are many who by now are tired of my coin analogy (I've used it many times on CS already ;p) so I'll refer those not familiar to it to my previous post explaining bit depth and dynamic range... just substitute dynamic range for gamut in this case

as for what Karl Lang wrote, well, it would be absolutely true if one didn't profile one's monitor... the colour represented by RGB values is dependent on the gamut of the output device and are not absolute values... if the gamut of the output device is large, then the difference between each RGB value gradation would be high...

but by profiling the monitor, the gamut of a monitor is mapped to a known standard (usually LAB nowadays) and with programs that are colour aware, those colour aware programs would take into account an image's colour space, whether sRGB, Adobe RGB, Prophoto RGB, etc. and translate it such that the colour produced by the monitor would be a known value...

thus, between two profile monitors, by having a certain image with a certain RGB value, say 255,0,0, if both monitors are properly profiled, they would give me the same red... and 254,0,0 would be different to 255,0,0 in each of these two monitors by exactly the same amount...

on the other hand, if the monitor does not have a gamut wide enough to produce a certain colour space (and most monitors can't even cover all of Adobe RGB), then the image's colour might be a bit off (how it is off would depend on the colour intent of the program but that's a whole different story) and that is something software would not be able to remedy completely... so, for me, I would rather want as much of a wide gamut as there is available and have the monitor properly profiled...

moral of the story: profile your monitor

 

[lennyl]

Thank you for the explanation. After reading your post and re-reading the Karl Lang opinion (which seems to be quoted all over the place) I realize 10 bit/channel monitors are just a small part of what he's talking about and not the main point at all.

Back to a Dell 2408WFP-HC - it has 110% of Adobe RGB gamut, or so Dell claims. So, if the monitor is profiled, and I'm displaying sRGB with a colorspace aware app, I should not see any difference with a decent monitor, assuming that the other monitor can display at least 100% of sRGB?

 

[theRBK]

Back to a Dell 2408WFP-HC - it has 110% of Adobe RGB gamut, or so Dell claims. So, if the monitor is profiled, and I'm displaying sRGB with a colorspace aware app, I should not see any difference with a decent monitor, assuming that the other monitor can display at least 100% of sRGB?

if both monitors are properly profiled, technically, yes... since I have neither the equipment nor the inclination to test Dell's monitor, taking their word on the gamut as correct, then it should be the case