DCI-P3 Wide Color Gamut
4K/UHD video is about more than just increased picture resolution. One of the other enhancements that is being support with Ultra HD Blu-ray discs and perhaps some streaming video services is a wide color gamut (i.e., increased color space). A wider color gamut means the resulting image is able include more saturated colors. HDTV uses a rather modest color gamut that is defined by the ITU Recommendation 709. For 4K/UHD ITU has defined a extremely wide color gamut as part of their Recommendation 2020 and the Ultra HD Blu-ray disc sytem has adopted Rec. 2020 as the 'container' for conveying a wider color gamut. That does not mean movies released on Ultra HD Blu-ray discs will actually be created for display using the full Rec. 2020 color gamut. Rather the color gamut can be greater than Rec. 709 and up to a maximum of the color gamut defined by Rec. 2020. It now appears that the movie studios plan to release their Ultra HD Blu-ray titles (at least for the next couple of years) using the color gamut already being used by the digital cinema industry and this is called DCI-P3. This is what you see in your local movie theater.
The JVC RS600U is only the 3rd projector we have reviewed that includes specific provisions for supporting the DCI-P3 color gamut. The other two were the Sony VPL-VW1000/VW1100 and the Epson Pro Cinema LS10000. All of these projectors make use of an internal color correction filter that can be moved into the projector's internal light path when the wider color gamut is needed. In the case of the Sony VW1000 (and the upgraded VW1100) the filter causes a noticeable light loss with the projected image being perhaps 20% to 25% dimmer with the filter in place. I was surprised to find that the filter in the RS600U decreases the light output by only about 8%. The Epson LS10000 falls between the JVC and Sony in terms of the amount of light loss its color correction filter introduces.
The bottom line is the RS600U can still project a very bright image when operating in a mode supporting DCI-P3 color gamut.
High Dynamic Range (HDR)
HDR is the second additional enhancement being introduced with 4K/UHD video. Just about all of the movies already announced for release on Ultra HD Blu-ray discs will include support for HDR and several of the streaming video services are also supporting HDR. However, there are outstanding issues with how projector will handle HDR content. This is because the movie studios, as part of the UHD Alliance, as well as the Blu-ray Disc Association have adopted characteristics for the consumer version HDR that assume use of a very bright display (think a very bright LCD flat panel display) asthe peak image highlights will be displayed very bright (e.g., 1000 NITS or almost 300 foot lamberts). No home theater projector will be able display more that a fraction (e.g., 10% - 20%, more depending on screen size and gain) of these peak brightness levels. The commercial digital cinema industry has defined a commercial version of HDR that has much lower peak brightness level requirements that would be applicable to home theaters, but that's not what is going to be used for the consumer video sources. So the question is although JVC and Sony claim support for HDR on some of their company's new projectors, will it be possible to calibrate these projectors to produce satisfactory results when connected to a consumer 4K/UHD source providing HDR enabled video. The RS600U offers a gamma setting that JVC indicates is for displaying HDR video, but will that actually be enough. At this point I do not have an answer to that question, but perhaps once Ultra HD Blu-ray players and the first wave of movies supporting HDR are released, around March 1st, I will be able to evaluate if HDR really works with the RS600U or if perhaps JVC will need to made some software/firmware updates to achieve improved compatibility.