Screenshot Comparisons 4K

[Penton-Man]

Originally Posted by pawel86ck

And here's explanation what HDR actually does
http://www.lightillusion.com/uhdtv.html

Pawel, I’m on your side as to being pro-HDR , but not sure if I would use the Light Illusion white paper as a definitive reference for although it does make some good points (like calling out the marketing hype trying to directly correlate the total dynamic range of the human visual system in a simplistic fashion to viewing content on a screen), it also contains misinformation.

For instance, he writes “the ST2084 HDR specification defines that reference white (normal diffuse white) is 100 nits” which is incorrect as that is not specified in ST 2084.

Additionally, he writes…”To actually gain benefit from the concept of HDR the actual viewing angle the display would need to occupy would be in the order of 45°, which with an average large TV of 55" would means sitting just 65" from the screen.”…..which I found misleading as previously explained in discussion with Kris Deering….
https://forum.blu-ray.com/showthread...t#post11652570

Also, it’s apparent that the Light Illusion white paper does not include the latest contributions/ provisions agreed upon so far during the last ITU meeting in Geneva, the greatest achievement being the new draft recommendation on the high dynamic range TV (HDR-TV).

[ray0414]

The problem with those screen shots is that the hdr metadata is not transfered through the entire chain that is required to get that picture to our screens we are using to view them on. I guess you could say it's an empty picture. The metadata isn't embedded in it.

[Penton-Man]

Originally Posted by Oliver K

I am also surprised...

Welcome back Oliver K (from Germany), long time no see.

[pawel86ck]

Originally Posted by Deciazulado

In other words take into account the SDR is a transformation of the higher contrast HDR grade which is expecting 1000 or more nits (10,000 = 100%)

But both pictures are SDR conversions from the same UHD disc, and still these pictures looks different. IMHO samsung player converted HDR to SDR differently, much better to my eyes.

[James Freeman]

Originally Posted by pawel86ck

Colors looks just weird on HDR->SDR Blu-Ray.com screenshot conversion.
Screenshots from "scorpiontail60" looked much better.

You must understand that when manipulating RGB values and clipping the higher values the image becomes more saturated.
I assume that the Samsung UHD player does some color manipulation also.
BTW, I can make the HDR image to look EXACTLY like the SDR by Blu-Ray.com with simple levels manipulation.

A frame from the standard bluray disc (resized to 4k):


HDR-> SDR by Blu-Ray.com:


HDR by Blu-Ray.com:

[dvdmike]

I say again, hmmmmmm

[pawel86ck]

You must understand that when manipulating RGB values and clipping the higher values the image becomes more saturated.
I assume that the Samsung UHD player does some color manipulation also.

I dont know, but THESE UHD SDR screenshots from blu-ray.com reviews looks weird to my eyes , while "scorpiontail60" screenshot looks normal.

Look at my comparison from post @378. In blu-ray.com screenshot picture is too dark, and these letters have obvious ringing, but on the right (picture from samsung player) there's no black crush, colors looks better and ringing isnt noticeable anymore.

[James Freeman]

Notice how the stripe on the NASA logo looks RED on the SDR-BD but on the HDR->SDR is orange like the notorious Flare.

[JoeDeM]

Originally Posted by Geoff D

So they're showing SDR ones and then HDR ones? The bottom set look very dull and washed out, presumably because I'm not able to apply the correct HDR EOTF to them on my monitor.

If those are legit then that's not exactly the greatest upscale I've ever seen on The Martian, there's some obvious aliasing on fine details here and there, and those compression artefacts are not pretty.

Last Witch Hunter is a bit more like it, though. Love the detail in that shot of Vin at the top. (The distortion that can otherwise be seen in some of them LWH shots is probably due to the movie having been shot anamorphic which is an educated guess, I haven't checked the tech spec for it).

And there is the problem, it's better if they don't show screen shots, as most people will just be looking at them on their computer monitor.

[bruceames]

lol, I thought the washed out pics were from the BLu-ray.

[bruceames]

Originally Posted by JoeDeM

And there is the problem, it's better if they don't show screen shots, as most people will just be looking at them on their computer monitor.

I have 5k monitor but it's not HDR (do they even make one?). But fortunately I can just check them out on the actual display since it has a built in browser. Obviously few people will do that though.

[Pieter V]

Originally Posted by bruceames.

lol, I thought the washed out pics were from the BLu-ray.

It shouldn't be washed out, even on my Full HD monitor. Especially those movies that are sharp filmed. If I Google on 4K wallpapers those are sharp too on my monitor.

Let's see how Sicario looks.

[James Freeman]

Here is my shot on converting from HDR ot SDR with custom S-Curve.

The top image is HDR.
Middle HDR->SDR by Blu-ray.com
My try HDR->SDR with custom S-Curve.



The conversion from HDR to SDR can be done much more gracefully and retain the HDR information instead clip it, yet still make it look natural.
Put some effort into it Blu-ray.com don't just move the slider down.

[42041]

Originally Posted by James Freeman

Here is my shot on converting from HDR ot SDR with custom S-Curve.

The top image is HDR.
Middle HDR->SDR by Blu-ray.com
My try HDR->SDR with custom S-Curve.

[snip]

The conversion from HDR to SDR can be done much more gracefully and retain the HDR information instead clip it, yet still make it look natural.
Put some effort into it Blu-ray.com don't just move the slider down.

Same shot from the 1080p blu-ray, for reference: https://www.blu-ray.com/movies/scree...65&position=24

[pawel86ck]

James Freeman@ your custom s-curve looks good, I like it

I have 5k monitor but it's not HDR (do they even make one?). But fortunately I can just check them out on the actual display since it has a built in browser. Obviously few people will do that though.

Bruceames@ but people with HDR HDTV can always check these HDR pictueres on their TV and based on that make their opinion whetever they like what they seeing or not. It's always better than nothing

[Opips3]

The top image is HDR.
Middle HDR->SDR by Blu-ray.com
My try HDR->SDR with custom S-Curve.

[Geoff D]

Originally Posted by bruceames.

lol, I thought the washed out pics were from the BLu-ray.

Hah! Now you really have been drinking too much of the HDR Kool-Aid, I think.

[James Freeman]

Originally Posted by pawel86ck

James Freeman@ your custom s-curve looks good, I like it

Well, it's how it should be done and IS done when grading the movie in the studio.
42041 posted a screenshot from the SDR blu-ray for reference.

I wonder how the Samsung or Panasonic do the conversion.... Clipping or S-Curve?

[Deciazulado]

Is interesting how the most effort is in criticizing and evaluating what is really a reduced straight conversion (so a placeholder for the real thing) from a higher quality format to a lower quality format, and in trying to horsehoe down the HDR image into looking best in SDR, eliminating the HDR, and not being interested in getting HDR. I see this every time a format changes. The Blu-ray has already done the best conversion/SDR representation thought by the original content producers. (I guess when P3 colors or 2020 ones are despicted too wild we'll have to desaturate then too)

[ray0414]

Originally Posted by pawel86ck

James Freeman@ your custom s-curve looks good, I like it


Bruceames@ but people with HDR HDTV can always check these HDR pictueres on their TV and based on that make their opinion whetever they like what they seeing or not. It's always better than nothing

I already tried. It just doesn't work like that. The pictures need to be embedded with hdr metadata to trigger the tvs ability to display hdr.