It seems the ‘next big thing’ in TV, besides 4K is High Dynamic Range, or HDR. From my very basic understanding it adjusts contrast dynamically, so very dark areas are adjusted to bring out the differences, and very light areas likewise. It is like adjusting a photo from under exposed and overexposed and merging the best of the 2. While perhaps not 100% accurate, I’m sure I’m in the ballpark.
One particular example I saw was amazing, on one side it was a star filled sky, though looking closely you could see the Milky Way. On the HDR side the galaxy was easily and beautifully displayed, almost in ‘supervision’ something that was hidden from our own everyday eyesight but there all along.
My question is why do we need a special TV to do this? Why can’t it be included in the original source stream to display a HDR type image instead of the regular one? Or why can’t streaming devices add HDR by just re-jiggering the image output to the TV to display a HDR image?
HDR can make some scenes look better. It can also make other scenes look worse. And “better” and “worse” are purely subjective. What looks better to one person might look worse to another.
A comparable issue is the loudness war for digital audio. Producers discovered that many people liked “louder” CDs. So they fudged with range and other settings to make CDs (and now audio files) seem louder.
All at the cost of actual sound quality.
The closer the image is to the original, for me, the better. Playing digital tricks just makes things worse.
Well, you don’t need a special TV to do what you’re talking about, which is to adjust the local dynamic range of different parts of the image in the video stream. But doing so is throwing away information in the source video. Maybe not useful information?
But different displays have different capabilities. So, if you make your video stream target a particular physical display dynamic range, then you essentially are compressing the dynamic range. And it might look kind of weird or distorted? I’m not sure.
I believe the idea of the new TVs is that they actually have greater dynamic range, so the video stream could be less compressed, and you could see more of what there is to see.
Specifically, I believe that in most cases TVs get greater dynamic range by having independent backlight regions. So, two pixels right next to each other still have a range of X, but the difference between pixels on different parts of the screen (with different backlight elements) could have a much larger range.
We have 4K Vizio with this feature, and I turned it off.
It worked well on certain scenes, but caused some very visible and annoying artifacts on many others. The image is just fine without it, IMHO.
You don’t quite have it right. HDR means that the TV itself is able to have more accurate colors and more dynamic range–meaning it can show both small changes in dark parts and also show full colors in the brighter parts. It’s a hardware thing.
What’s going on right now is that we don’t actually have any HDR images, so the TV tries to convert lower quality images to HDR. Just like that increased frame rate, it doesn’t always do a good job.
The terminology is confusing, since what you are describing is true for HDR photography, which very well can just use existing tech and special software. Honestly, I think they should have picked a different acronym. Maybe WDR–wide dynamic range.
Yeah, it also reminds me of the nonsense regarding Sharp’s Quattron TVs.
They add a 4th color to their screens. Except they don’t really. Plus there are no sources with the 4th color. So they fake it by shifting the color range in the yellow area. And there really isn’t much unused color space in the standard NTSC color diagram anyway.
So some yellow objects, the fish in the TV ads where George Takei does his “Oh, my!” look a brighter yellow. But what if that fish wasn’t really that shade of yellow to begin with?
Imagine the uniforms of a football team with yellow jerseys getting their actual color shifted. Don’t think the fans would like that.
Trying to fake something that isn’t in the original signal is just a bad idea.
I’m afraid you are mistaken. HDR video is not like HDR digital photography. A true HDR TV or projection system is capable of displaying a *much *wider dynamic range than conventional disaplays. According to Wikipedia, a standard dynamic range image has a dynamic range of 6 stops and an HDR video image has 17 stops. In short, this means the display is capable of much, much brighter whites, far beyond what a standard set is capable of producing.
However, an HDR set needs *content *with a higher dynamic range. That means you must be watching an HD Blu-ray or 4K streaming content that was mastered in HDR. Unfortunately, there is relatively little of this so far. So what you and others here may have perceived as underwhelming imagery was very likely SDR material that the HDR set was trying to enhance. Obviously, this will be far less impressive than real HDR content.
In cinemas, there’s Dolby Vision, which in North America is now exclusively available in certain AMC theaters. Here’s a list of Dolby Cinema at AMC Prime theaters.
Although I don’t have much experience with HDR TVs, I have seen Dolby Vision several times, and it is spectacular. Amazingly bright (31 foot-Lamberts, compared to 14 for standard cinema), with incredible amounts of detail in the shadow areas. If you have an AMC Dolby Cinema near you, go and see a movie there. You’ll never want to watch a movie in a regular theater again.
HDR is the exact opposite of what you’re describing. The loudness wars reduced dynamic range. “Loud” sounds good in a noisy environment, because you can hear the quiet bits over the ambient noise. But it sucks if you have any kind of reasonable listening setup.
HDR, as advertised, gives more dynamic range. And as it turns out, it gives better demos too, because it’s combined with a higher peak brightness.
As others have said, faking LDR content into HDR is a waste. But true HDR content is amazing. Our eyes have something like a million to one dynamic range, but current tech is less than a thousand to one. HDR expands that range considerably.