One of the best-kept secrets in technical conferences is the annual Hollywood Post Alliance Technology Retreat, held in Palm Springs in late January and early February. This low-key event brings together over 250 movers and shakers from the Hollywood community as well as broadcast networks, HDTV manufacturers, direct broadcast satellite networks, the government, the MPAA, Washington DC insiders - you name it, they’re all in attendance.

There were numerous technical papers presented this year on display-related subjects, and one of the best was delivered by Jeroen Stessen of Philips Applied Technologies in the Netherlands. Stessen’s topic was "Extended Color Gamut for Consumers: The Display Side."

Stessen’s talk covered the basics of color gamuts, delving into source gamuts for various types of image capture and then moving to display gamuts, such as the REC.709 standard for digital TV and HDTV. Stessen then went on to discuss color space conversion and gamut re-mapping, neither of which is as easy as it sounds.

Stessen then showed some typical color gamuts from current HD consumer displays, including LCD panels with CCFLs and plasma display panels. In most cases, the raw color gamuts from all of these displays create a space that far exceeds the REC.709 standard - but not in a linear fashion.

If the green coordinate shifts too much towards blue, it will be problematic to correct it to the REC.709 green, which has more yellow in it. If the red coordinate is undersaturated, it may not be possible to shift red and yellow values enough to pull the green back into line. In fact, it may be impossible to make some corrections to the red channel as they could require negative values of luminance.

Stessen’s paper was timely for me, as I was in the midst of testing four large flat-panel HDTVs, all with 1080p resolution. Two were plasma monitors, and two were integrated LCD HDTVs. And none of them could hit the REC.709 coordinates on the bulls-eye; even though their raw color gamuts all exceeded the 709 space.

The problem? One of the LCD monitors measured with a green coordinate that had much more cyan than yellow in it, making a REC.709 gamut re-mapping job difficult at best. The other was under-saturated with green and red. The two plasma monitors fared better with greens shifting more towards yellow, but neither of them could hit the "709 bulls-eye," either.

On the face of it, you’d think that plasma monitors would have the easier task here, since they also use color phosphors. But the choice of the green phosphor formulation seems to be crucial to getting a high score on the shooting range. Add more cyan/blue to the mix and you increase luminous output, making the panel brighter - an important consideration for the consumer marketplace. And there are other trade-offs manufacturers can consider.

On the face of it, achieving 100% of a known color space standard shouldn’t be too difficult. Yet, we have display manufacturers bragging that they far exceed the NTSC standard (hello - remember REC.709?) and that they can achieve super-saturated, radioactive greens and reds with CCFLs, LEDs, and even lasers.

Guess what, guys: Brute force isn’t the answer when it comes to color. It’s one thing to buy a high-powered rifle, but it’s quite another to use it skillfully and accurately at the shooting range to get the highest possible score.

Manufacturers of LCD, plasma, and emerging display technologies and light engines would do well to focus first on their "compulsories" - precisely matching internationally-recognized, standard color spaces used for encoding video and digital cinema content - and only then move on to more advanced targets, such as newer and wider color spaces.