NAB 2018 didn’t showcase any startling new tech — no new minivan-sized light-field camera; no “Billy Lynn’s Long Halftime Walk” — but it was definitely a show where former “science projects” appeared as solid, production-ready products. (And no, that minivan-sized light-field camera was not among them.) For me, the two most noticeable trends were the transition of direct view cinema screens from “curiosity” to “product”, and the growing availability of next-gen TV tech: 8K, HDR, and ATSC 3.0.
Direct View Cinema Screens
Direct view cinema screens are an evolution of “LED video billboard” tech: high-brightness modular panels seamlessly assembled into large screens. The two current leaders are Sony’s Crystal LED and Samsung’s Cinema LED Screen, but the rest of the industry is catching up fast.
What makes these different from the video billboards seen all over the Vegas Strip and in your local sports arena is a very tight pixel pitch, a minuscule fill factor, and completely insane brightness levels.
Pixels on these screens are typically 1.2 to 2.5 mm apart, closely spaced enough that if you’re a few feet back from the screen you see a smooth and continuous picture. Furthermore, the fill factor — the area of a pixel actually occupied by a light-emitting element — is absurdly low: Sony says that more than 99% of the CLED pixel area is dark, meaning less than 1% of a pixel consists of actual LEDs. That means the remaining area is (a) available to be used for the join between two modules without any visible seam or alteration in pixel pitch, and (b) can be blacked out to increase contrast ratio.
What makes it all work is that those tiny, pinpoint LEDs are unbelievably bright. Even with a <1% fill factor, Sony quotes a 1000 nit peak brightness (Samsung is more modest, claiming a mere 500 nits, which is still astonishing). If you look at one of these screens up close, the impression is of tiny points of light that grow as they brighten.
The pixels don’t grow, really: reflections, flare, and blooming in your eye (or in the camera) make the pixel appear to grow as it glows. It is, however, simply going from “rather bright” through “exceedingly bright” all the way to “harmfully, painfully, frighteningly bright”.
This sort of performance does not come cheap. One vendor quoted a cost of $10,000 / square meter; I overheard a Sony chap say that the CLED screen runs about $34,000 per panel (about 18″ x 16″).
It’s also not perfect yet: surface reflections can be an issue:
LEDMAN showed a variety of products with pixel pitches from 2.4mm up to 5.95mm:
How do you wire these things? The LEDMAN system’s exposed connections make it visible: both power and data are daisy-chained through the modules using standard AC and Cat5E data cables.
A separate display processor scales the image as needed and packetizes the data for each panel. These displays reach 800 nits and max out at 480 watts / square meter.
CREATELED showed off screens as fine as 1.4mm between pixels and up to 1000 nits in brightness. As their “booth banner” indicates, you aren’t limited to boring, flat, two-dimensional screens only.
CREATELED also uses daisy-chained cables…
…while COLEDER‘s Ace Block modules snap together using a cable-free design:
Ace Blocks run as fine as 0.9mm / pixel or as coarse as 2.5mm.
There were plenty of other big-screen suppliers, too; video billboards have long been a viable market. As the pixels get smaller and brighter, product lines that previously only worked for advertising and sports displays migrate ever closer to cinema-quality screens.
Next-Gen TV: HDR, 8K, ATSC 3.0
The Tokyo Olympics are only two years away, and Japan has decreed that the Tokyo Olympics shall be broadcast in 8K, High Dynamic Range, and Wide Color Gamut. These sorts of self-imposed deadlines are great drivers of development, and several vendors showed practical 8K broadcast cameras at NAB.
Sharp’s $77,000 8K camcorder is notable for how normal it looks. Yes, it has a prominent fan on the right side and four 12G SDI connectors for the uncompressed live signal —and prominent “8K” labels — but those aside it’s not something you’d do a double-take at.
Hitachi offers HDR capability across their line of HD, UHD, and 8K cameras.
So far, 8K broadcast cams and ‘corders are built around S35mm-sized single sensors. Some use built-in optical expanders and standard B4-mount broadcast lenses; others offer PL mounts to which you can fit an expander like the HDx35 on this VariCam when you want to rock a broadcast zoom:
HDR, along with WCG (wide color gamut) are part and parcel of the Rec.2020 broadcast standard, and they’re just as viable in HD as in higher resolutions. Indeed, US broadcasters are more bullish on HDR/WCG than on UHD: better pixels instead of more pixels, and Rec.2020 is baked into ATSC 3.0 transmission standard.
For the foreseeable future HDR and SDR will need to co-exist, even for the same program feed. Every camera vendor playing in this space offers simultaneous HDR and SDR outputs from their CCUs (camera control units), and folks like FOR.A offered standalone boxes to cross-convert between HDR and SDR along with up/down/cross-conversion of frame sizes and frame rates.
Version 6.0 firmware for the Panasonic VariCam LT added “VariCam Live” capability, so that the VariCam can be shaded from a remote panel like any other broadcast cam. You can paint the camera in HDR and then tweak the SDR outputs directly using “SDR convert” controls:
The ATSC 3.0 booth in the lobby outside Central Hall featured an autonomous vehicle:
A similar autonomous bus trundled ’round a route between Central and South Halls, with monitors displaying ATSC 3.0 feeds from an experimental transmitter 12 miles away.
I can confirm that the feed never froze or broke up as the bus navigated between buildings and past tall stacks of shipping crates. The bus, however, got “confused” at one turn on its route — someone had moved a barrier fence slightly closer to its path — and our bus monitor had to pull out a standard game controller (!) and joystick the reluctant vehicle past the threatening fence.
I’m sure there’s some deeper meaning in this incident, but darned if I can figure out what it is.
While ATSC 3.0 may still be experimental here, it’s already being rolled out in South Korea:
South Korea’s booth in the “Futures Park” section of North Hall showcased all aspects of ATSC 3.0 development. Nearby, NHK’s 8K theater screened three programs of HDR 8K/60p with 22.2 audio on a 350-inch screen. It was rather nice, but it wasn’t hugely different from the similar demo last year. This is as it should be: 8K/60p isn’t a science project any more, it’s a practical, well-developed technology, ready for commercial deployment.
NHK starts satcasting 8K/60p to Japanese viewers later this year, and they had three demo “living rooms” set up to show it off. The low-end room had a 70″ LCD and two-channel sound; the midrange room had an 85″ screen and a line-array speaker with binaural processing; the high-end room featured a 95″ 8K set and discrete 22.2 audio.
After spending time at NHK, I wandered over to the adjacent UHD Alliance booth to look at codec comparisons and frame-rate studies. For a minute, I wondered why the pictures looked so coarse and blocky. Then it struck me: they were only 4K.
Disclosure: I attended NAB free on a press pass but paid all my own travel / food / lodging expenses. There is no material relationship between me and any of the vendors or organizations mentioned and nobody offered payment / bribes / blandishments of any sort for coverage.