TV tech

[Aleron Ives]

Originally Posted by haertig

when playing SDR content, I can go to settings while the film is playing and observe that my backlight intensity is 65%. That indicates SDR. But when I am playing HDR content, I can go to settings and I find my backlight has been turned up to 100%. This is because the control info in the HDR content subsequently instructs the backlight to alter its intensity for different parts of the image.

Wow. That sounds... awful. My eyes are extremely photosensitive, which is the main reason why I bought an e-reader in the first place. Even with my monitor set at 5% brightness, reading on a PC for extended periods is physically painful. I have my TV set around 30% brightness for the same reasons.

If HDR allows the Blu-ray player to take control of my backlight against my will, then I will make a point of permanently avoiding HDR. Thanks for the warning.

Originally Posted by JSWolf

Most TVs made these days are 4k TVs. So if you were to ever replace your TV, would you get a 4k TV or would you look for another HD TV?

I use a 720(768)p 26" TV, and my understanding is that TVs this small are hard to come by these days. The largest size I would accept would be 32", and this size isn't even usually 1080p anymore, let alone UHD, so I think I'll be able to find a non-UHD replacement when the time comes. I'm quite happy with my TV, so I hope that's a long time from now.

[haertig]

Originally Posted by Aleron Ives

Wow. That sounds... awful. My eyes are extremely photosensitive, which is the main reason why I bought an e-reader in the first place. Even with my monitor set at 5% brightness, reading on a PC for extended periods is physically painful. I have my TV set around 30% brightness for the same reasons.

"Brightness" and "Backlight Intensity" are two separate settings.

[Aleron Ives]

I think most people associate the term "brightness" with the backlight intensity (for LCD), rather than colour tuning, but yes, I was talking about the backlight.

[JSWolf]

Originally Posted by Aleron Ives

I use a 720(768)p 26" TV, and my understanding is that TVs this small are hard to come by these days. The largest size I would accept would be 32", and this size isn't even usually 1080p anymore, let alone UHD, so I think I'll be able to find a non-UHD replacement when the time comes. I'm quite happy with my TV, so I hope that's a long time from now.

Samsung has 2 32" 4k TVs.#
https://www.samsung.com/us/televisio...22+and+smaller

[Aleron Ives]

I find that rather shocking, honestly. According to conventional wisdom, you'd have to sit about 2' away from a 32" TV in order to get the full benefit of 2160p. That's more like a computer monitor than a television.

[haertig]

Originally Posted by Aleron Ives

I find that rather shocking, honestly. According to conventional wisdom, you'd have to sit about 2' away from a 32" TV in order to get the full benefit of 2160p.

Many people with 4K TVs don't sit close enough to be able to discern the difference between 1080p and 4K. Our main TV is 70", and we sit - eyeball to screen - exactly 13' away from it on our couch. That's solid 1080p territory. 4K is of no benefit (but HDR is).

That's more like a computer monitor than a television.

My main monitor is 29", my wife's is 32". Neither is 4K, but with normal computer seating positions, both would benefit from it.

[OtinG]

Originally Posted by Aleron Ives

. I'm sure HDR does look a bit better than SDR, but is it really that much of a leap?

True HDR looks a lot better when viewed on a good 4K HDR screen.

• SDR is 8-bit color, meaning you get about 16 million colors, and thus some, or a lot of, color banding.
• True HDR is 10-bit color, meaning you get about 1 billion colors, and thus less color banding, if any, and more brilliant and true to life color.
• True HDR often brings with it a much brighter screen to allow much greater detail in shadows and in bright areas.

Cheap 4K TVs don't always have true 10-bit color or HDR though, so don’t expect it to look much better than on a comparable full HD screen. But when viewed on a good 4K TV (or monitor) with true 10-bit color and HDR, true HDR will be many times better looking than SDR.

Having said that, good luck finding much true HDR content to view. Cable and satellite typically use 720p content, but some use 1080i. Broadcast TV uses 720p or 1080i content as well. Most streaming services with cable-like channel programming use 720p or 1080i. These formats tend to scale up nicely with more modern equipment that contains up to date processors. But it will still just be 4K SDR, so decent 4K image but with only 1/60th of the colors and a dimmer screen that clips blacks in shadows and whites in bright areas. Some streaming services like Netflix, Apple TV, Amazon’s Prime Video, etc. offer some content in true 4K HDR, but most content is still in SDR.

When I view most content which is SDR on my Sony Bravia 4K TV it looks really great, even though it is likely upscaled from 720p or 1080i. When I view true 4K HDR content the WOW factor kicks in! It can look like the view through one on my windows. That is, pretty much what my eyes are designed to see. It is bright, crisp, more natural colors, and a much higher dynamic range of light that is closer to what our eyes are designed to see. My TV is around $800 brand new, so not a high end model by any means. If you spend way more, the picture quality will be even more impressive, but I’m happy with what I have.

If you ask me if it is currently worth upgrading to a good 4K HDR TV I must say it depends on how much HDR content you can actually get. There is enough HDR content available to have made it worthwhile for me, but there might not be enough for some people.

[Aleron Ives]

Originally Posted by haertig

Many people with 4K TVs don't sit close enough to be able to discern the difference between 1080p and 4K.

That's true. It's mostly a matter of price. If the UHD set is the same price as the 1080p set at the same size, then you don't have much of a reason to buy 1080p; however, it looks like a 32" Samsung is still $500, whereas a 720p set would be under $200, so I can't see paying more than double when the UHD isn't going to give any added benefit.

Originally Posted by OtinG

Having said that, good luck finding much true HDR content to view.

That's a problem with UHD, too. Many UHD Blu-ray movies are simply upscaled from 1080p, and the palette has been tinkered with so that it looks different from the Rec.709 release, even though it's not actually a wide gamut or HDR source.

[mpeg2]

There's also some marketing/education aspects here. The camera industry has trained folks that more pixels is better (the ever increasing resolution of the camera sensors). So, when people see a TV with 4K resolution advertised versus a 1080 one (1/4 the "dots"), it must be better. Try to explain some of the other aspects of UHD to the average viewer that hasn't experienced them (HDR compared to SDR, Wide color gamut, higher frame rate and even higher quality audio (which might be more important than the video itself)) - and you'll likely be met with blank stares. Many industry studies have shown that increased dynamic range has a huge WOW factor, while higher resolution at normal screen sizes/viewing ranges doesn't.

So, the TV industry has learned to advertise 4K TVs instead of the other aspects.

BTW, with the advent of the NextGen TV (ATSC 3.0) which is now being broadcast in most of the country, all of the UHD features can be delivered over the air (and with no subscription cost)...

[Aleron Ives]

Originally Posted by mpeg2

There's also some marketing/education aspects here.

Yes, especially in the US, TV makers made huge profits during the transition to digital TV in 2009, and they started expecting people to replace their TVs every few years so they could keep profits up. When 3D didn't entice people to replace their TVs again, they switched to touting UHD, instead.

I'm honestly more interested in wide gamut than HDR. Is it possible to have one without the other? UHD BD should support both if your TV does, but I don't know if you get any choice over which ones are used.

[mpeg2]

Originally Posted by Aleron Ives

...
I'm honestly more interested in wide gamut than HDR. Is it possible to have one without the other? ...

I think it is up to the content creator to figure out which features of UHD are used - but the TV settings might allow you to choose which to select for viewing. Done correctly & with appropriate content, the combo of HDR & wide color gamut can be incredible.

[Aleron Ives]

There's also the problem that the vast majority of content you'd ever want to watch has already been made, so unless it's possible to re-scan old movies and TV shows to get wide gamut HDR, then you may never find anything you want to watch that offers both features. I have no idea how the gamut and dynamic range of film compares to various digital video standards, but that's going to be your source material for 99% of old content.

[mpeg2]

Originally Posted by Aleron Ives

There's also the problem that the vast majority of content you'd ever want to watch has already been made, so unless it's possible to re-scan old movies and TV shows to get wide gamut HDR,

It is possible & is quite commonly done (and has been for quite a while) - stuff that was shown before the digital conversion was set up for CRT TVs (and the 4:3 aspect ratio). When you see the same movie on an HDTV in a 16:9 aspect ratio, a rescan has been done. Of course changing aspect ratio is pretty easy - doing HDR and wider color gamut takes a skilled person to make the decisions and tweaks.

[Aleron Ives]

I know that you can rescan film to get a 1080p version, but I don't know whether film has enough detail to support 2160p or 4320p. If HDR and Rec.2020 gamut are beyond what film can handle, then it's hard to say that you're being true to the original movie if somebody uninvolved in creating the movie is tweaking the dynamic range and palette decades later to make an HDR and wide gamut version that looks nothing like the original film. Since those decisions are going to be subjective, it seems like you're creating a different, but not necessarily better, version of the movie.

[mpeg2]

I believe that movie film has much more resolution than 4K. Quite often the original studios or creatives are involved in the process of conversion - its quite common for the original intent to be met (or even exceeded). I recall watching some of the work involved with a redo of Easy Rider - including cleaning up a once thought to be lost reel of film. The processing was quite intense.