Eric Gemmer, senior video engineer at THX, talks about the process of THX video certification, the improvement of 3D performance, active versus passive 3D glasses, home versus professional color gamuts, 4K displays and content, 4K upscaling, screen uniformity, factory calibration and manufacturing tolerances, answers to chat-room questions, and more.
Editor, AVS Forum
Very nice interview. (I particularly enjoyed the "Manpacks" segment. Sort of the webcasting equivalent of the old soap ads.) Great questions and answers, esp. on the difference between Rec. 709 (2K) and the new Rec. 2020 (4K) wide gamut spec, and how those may (or may not) be implemented on future TVs. (Maybe I'll have a reason to upgrade my old 2002 Sony XBR CRT after all.)
If Rec. 2020 is deployed for home video (which would be a good thing imo), hopefully it doesn't produce the same color-twisting issues as the Rec. 601 to Rec. 709 conversion. The Rec. 2020 gamut appears much wider than 709 though, so I'm guessin those differences would be easier to spot and fix than the comparatively small differences between 601 and 709.
I completely concur with Eric though that Rec. 709 can look very colorful indeed on a properly-calibrated display. When it's done right, the calibration process shouldn't necessarily make colors more saturated, but it should improve the definition of colors in video making the various hues in an image more distinct from one another (which may make them appear better saturated than on a poorly-adjusted display).
Some good thoughts on sharpness and uniformity as well. I'd been wondering about the differences between edge-lit and full-array LEDs after encountering those terms in recent AVS discussions, and Eric covered the subject beautifully.
A couple thoughts on the issue of Sharpness... Turning it all the way down may work ok on some displays, but it's definitely not the best strategy on all TVs, because many will begin to smooth-over the details at lower settings (my CRT certainly does). IMO, you want sharpness set high enough to clarify the detail that's there, but not to embellish or enhance it.
A good test case I've found for that is the recent Blu-ray release of The Spy Who Loved Me, which has very fine detail, and virtually no edge-enhancement (that I can see anyway) in the image. If you see any EE on a film like that, chances are that it's coming from your display (or possibly the player), rather than the actual encode of the film on the disc. The fine cel edges in some recent traditionally animated features can also be a good test, because those will pick up any EE in the display quite easily. These are sort of ideal scenarios though. And in some rare cases you may actually want a little smoothing to tone down the EE in a particularly bad transfer.
1:1 pixel mapping really should have eliminated the need for the Sharpness control (on 1080p sources like Blu-ray anyway). But most TVs do some scaling which can introduce unwanted artifacts or smoothing. Even 1080p TVs with no overscan may scale 1080p content on a subpixel level.
IMO, the detail is actually a bit "cleaner" in TSWLM (some might even say too clean or "Lowry-ed") than in the recent BD release of Lawrence of Arabia, which also has an impressively high level of detail, but with a slight impression of edginess. Maybe others here can offer some other suggestions along similar lines.
I'd like all HDTV displays to be "THX certified" out-of-the box btw... That is to say, Rec. 709 compliant within certain tolerances in at least one picture mode. Doubt that'll ever happen though, because there probably isn't any tangible benefit to the video manufacturers (unless compliance is required to access the US video market). As one of your other recent guests pointed out though... color is information. And if a display isn't correctly adjusted, then you're not getting the right information.
I found some of Eric's comments on the TV manufacturing process interesting as well, particularly his remark that the different display modes on TVs (ie "Standard", "Cinema", "Warm" etc.), are essentially just offsets of the "Vivid" mode that are plugged in by the manufacturer. Unless I'm mistaken, the THX modes would also be offsets of Vivid mode, because the Vivid mode is usually the native color of the display and its illuminants, which is as bright as the TV can go (hence "Vivid"). It sounds like the THX mode gets some more personal attention and adjustment on the production line though by some mfrs.
Had a few more thoughts on Sharpness as well, but maybe I'll save those for another time/place cuz there doesn't seem much interest here in that subject.
One small housekeeping note, Scott. Leaving the Text Color in the first post set to "Automatic" (rather than Black) makes it easier to read for users who prefer to navigate the site with the AVS Black skin*.
(*The different site skin modes are set in the Visual Preferences section of the Account Details in the user Profile btw.)