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Coloreason

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What color space is the NTSC used in monitor specifications?
« on: September 08, 2011, 03:03:40 pm »

What color space is the NTSC used in monitor specifications?
Although at the moment I can't find others, I've seen more than one source similar this one http://compreviews.about.com/od/monitors/a/LCDColorGamut.htm which says, quote:
"NTSC was the color space developed for the widest range of colors that can be represented to the human eye. Many may think that this has to do with the television standard group that it is named after, but it is not."
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digitaldog

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Re: What color space is the NTSC used in monitor specifications?
« Reply #1 on: September 08, 2011, 03:15:41 pm »

What color space is the NTSC used in monitor specifications?
Although at the moment I can't find others, I've seen more than one source similar this one http://compreviews.about.com/od/monitors/a/LCDColorGamut.htm which says, quote:
"NTSC was the color space developed for the widest range of colors that can be represented to the human eye. Many may think that this has to do with the television standard group that it is named after, but it is not."

Doesn’t sound right to me! He’s confused. I think he means CIE XYZ (1931).
I just plotted the gamut of NTSC 1953 in ColorThink Pro, its pretty similar in size to Adobe RGB (1998). It ain’t close to being as wide as CIE XYZ (based on human vision). Its gamut volume is reported at 1,299,090 while Adobe RGB is 1,207,520.
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Coloreason

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Re: What color space is the NTSC used in monitor specifications?
« Reply #2 on: September 08, 2011, 03:57:33 pm »

Thanks,

this makes me think, why on earth they chose to use NTSC as a color gamut reference in monitor specs. I wonder how many people actually understand what that exactly means. It would've been clear to anyone if the spec was called  "% of visible spectrum" as represented by CIE XYZ.  But then from the marketing perspective the number may not look so good to customers but if that was a reason then they should have used "% of sRGB". Doesn't make much sense either way.
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digitaldog

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Re: What color space is the NTSC used in monitor specifications?
« Reply #3 on: September 08, 2011, 04:43:13 pm »

This post from the ColorSync list might clear some of this up:

Quote
At 02:02 PM 11/25/2007, colorsync-users-request@lists.apple.com wrote:
> 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.
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Schewe

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Re: What color space is the NTSC used in monitor specifications?
« Reply #4 on: September 09, 2011, 03:47:47 am »

"NTSC was the color space developed for the widest range of colors that can be represented to the human eye."

Well, back when I was shooting film commercials intended for TV, the term NTSC was commonly called "Never The Same Color" because, well the moment a video signal hit the broadcasters and went over the air, who knew what the hell the colors looked like...

Kinda like the web today...

Seriously, I would not attach any significance to NTSC...
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