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Ask Slashdot: Why Don't HDR TVs Have sRGB Or AdobeRGB Ratings?
dryriver writes: As anyone who buys professional computer monitors knows, the dynamic range of the display device you are looking at can be expressed quite usefully in terms of percentage sRGB coverage and percentage AdobeRGB coverage. The higher the percentage for each, the better and wider the dynamic range of the screen panel you are getting. People who work with professional video and photographs typically aim for a display that has 100 percent sRGB coverage and at least 70 to 80 percent AdobeRGB coverage. Laptop review site Notebookcheck for example uses professional optical testing equipment to check whether the advertised sRGB and AdobeRGB percentages and brightness in nits for any laptop display panel hold up in real life.
This being the case, why do quote-unquote "High Dynamic Range" capable TVs -- which seem to be mostly 10 bits per channel to begin with -- not have an sRGB or AdobeRGB rating quoted anywhere in their technical specs? Why don't professional TV reviewers use optical testing equipment that's readily available to measure the real world dynamic range of HDR or non-HDR TVs objectively, in hard numbers? Why do they simply say "the blacks on this TV were deep and pleasing, and the lighter tones were..." when this can be expressed better and more objectively in measured numbers or percentages? Do they think consumers are too unsophisticated to understand a simple number like "this OLED TV achieves a fairly average 66 percent AdobeRGB coverage?"
This being the case, why do quote-unquote "High Dynamic Range" capable TVs -- which seem to be mostly 10 bits per channel to begin with -- not have an sRGB or AdobeRGB rating quoted anywhere in their technical specs? Why don't professional TV reviewers use optical testing equipment that's readily available to measure the real world dynamic range of HDR or non-HDR TVs objectively, in hard numbers? Why do they simply say "the blacks on this TV were deep and pleasing, and the lighter tones were..." when this can be expressed better and more objectively in measured numbers or percentages? Do they think consumers are too unsophisticated to understand a simple number like "this OLED TV achieves a fairly average 66 percent AdobeRGB coverage?"
This.
Also most people do not know, or care to know, the intricacies of yet another rating system.. let alone a Proprietary one.
Because 99.95% of consumers don't give a shit.
Lots of good answers already, but the simplest is hardly anyone outside certain industry's have any idea of color space. Try explaining how monitor color and printer color work is like trying to explain physics to a toddler. (generally speaking) It shouldn't be that hard, but somehow. most people don't get the concept until their image comes back with pink rather then red.
I think you're mistaken, at least in your terminology, and probably in over-generalizing. A standard 16:9, TV (1080p or 4k) has a physical size ratio of 16/9 =~1.78, exactly the same as the pixel count ratio of 1920/1080. The pixels are geometrically square, unlike, for example, most pre-SVGA computer resolutions (where 320x240 and 640x480 were the only common ones with square pixels).
Now, when you get into subpixels things may get more complicated, but browsing rtings, which includes magnified views of the subpixels, it appears that many/most large LCD TVs use the same adjacent rectangle RGB subpixel patterns common in LCD monitors. Bayer patterns are relatively uncommon, though perhaps they are more common among cut-rate TV brands.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Yup. Most people will never really appreciate how well the TV does on color as long as it's good enough. But many of us will notice that it doesn't have enough connectivity.
My big gripe is smart TVs that have a nice interface for selecting inputs, but don't have enough so you end up needing to use a switch, so you're back to a separate interface for selecting inputs. You can never have enough inputs, but they could be a lot less stingy. If you figure a cable box, a disc player, two gaming systems, and a streaming device, that's five inputs.
Perhaps there's only one game console, but eventually you'll get a new one, and then you may want to play some of the old games. Perhaps the TV has a good streaming solution built-in. Still, you don't want to run out, and adding HDMI ports should be dirt cheap.
Part of the problem has to do with the "white" LEDs used for backlighting the LCD -- the exact nature of their "white" varies slightly from batch to batch. Expensive TVs (usually) make a point of using "white" LEDs that are from the "best" batches/bins (consistency from LED to LED, color purity, etc). Cheap TVs use "white" LEDs from the lower batches/bins. The cheapest Black Friday TVs use whatever LEDs were left over after making the "main" manufacturing run.
So... you might have a TV made by someone like Samsung with a model number like MHD4kQ62 that gets made with the best LEDs... then a model with similar (published) specs that uses the cheaper LEDs & has a model number like MHD4kQ62SXB that sells for $100 less at Best Buy, and an additional model that once again has similar published specs, but uses the cheapest/leftover LEDs, has a model number like MHD4kQ62SVW and sells for $27 less than the Best Buy version at Walmart (possibly with fewer HDMI inputs, just to further spite buyers and shave another 25 cents from the manufacturing cost).
The point is, they don't talk about THOSE performance specs, because they don't WANT to talk about those performance specs. By not talking about them, they can let Walmart have a model that looks almost the same on paper, even if it's egregiously inferior if you saw it side by side with the most expensive variant.
Another area where they often cut corners: the timing circuit that allows a TV to natively deal with 50hz and 60hz, instead of being locked to 50hz OR 60hz native. It only saves a few cents because it's mostly just a few passive components omitted from the mainboard, but they do it anyway (especially with US models) because they know that 98% of US buyers won't notice the difference anyway.
"Do they think consumers are too unsophisticated to understand a simple number like "this OLED TV achieves a fairly average 66 percent AdobeRGB coverage?""
Er.... yes?
I had someone ask me what HD was, I've had people watching an SD channel on an HDTV and not realising that it's not "automatically" HD (the HD version of the same channel was higher up in the list), I've had people not understand that the remote control has to point at the TV (increasingly common again as a youth accustomed to Bluetooth are thrown back into an IR world).
Hell, I had one 18-year-old at work bring me their aerial and say "I found this in my room, I dunno what it is do you want it back?" and only correlated this with his lack of TV reception when it was pointed out that it was in fact still necessary to receive digital TV over the air (but they didn't care because they streamed everything).
I couldn't give a shit about sRGB etc. and I'd have to read up on what they even meant without this summary. You can be damn sure that most consumers don't even know what HDR is (they'll think it's something to do with HD!), let alone care about an arbitrary standard to do with it.
"Can I see it from an angle?" will be a question asked a million times more than anything to do with colour calibrations, nits, or anything else.