At 02:02 PM 11/25/2007, firstname.lastname@example.org
> On 11/23/07 9:45 PM, "Chris Murphy" wrote:
>> 2490 and LED do. But not the 2690, so the white point is a bit off
>> which you can compensate for. It's not off by much.
> Isn't the 2490 the sRGB unit and the 2690 the wide gamut (93%)?
Correct. 93% of Adobe RGB (1998), whatever that means. And the LED is
108% of Adobe RGB (1998), again whatever that means.
To clarify what this means, since there is a lot of confusion about this in the industry (intentional or not):
The de facto standard when throwing around display gamut sizes is currently to quote the gamut area, calculated in CIE xy, relative to a reference gamut and expressed as a percentage. If the reference color gamut is unspecified, it is generally assumed to be NTSC (1953)
- (which is pretty useless since it's not in use and makes things more confusing, especially for those doing video work).
Another confusing point about this figure is that it does not say what portion of the 2 gamuts overlap, so it would be possible to have a very large % gamut area, but only have a smaller portion of it actually covering the reference gamut.
At NEC we have started to quote 2 sets of figures: "Percent Area" and "Percent Coverage".
The "Percent Area" is simply the area in CIE xy of the display gamut vs the reference gamut, with no consideration of how much of the gamuts actually overlap. This value can be > 100%.
The "Percent Coverage" is the overlapping area of the 2 gamuts expressed as a percent of the total area of the reference gamut. The maximum possible value for this is 100%.
We generally quote these values for AdobeRGB and sRGB, so it is easier to determine which color gamut best suits a particular application.
Using CIE xy is not ideal because it overemphasizes the greens and under emphasizes the blues. A much better way would be to use CIE u' v', but that would probably cause more confusion and make direct comparisons even more difficult.