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Old 15th April 2024, 01:31   #64681  |  Link
huhn
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https://www.itu.int/dms_pubrec/itu-r...3-I!!PDF-E.pdf
have a nice read.

the important part is there focus on CRT. so it'S supposed to be used event through we clearly know they didn't look at bt 1886 well we also know they did because bt 1886 is gamma 2.4 on perfect black displays. and on none perfect black display like CR 1000 it is even brighter in black parts then sRGB is.

i can tell you they didn't use the bt 709 curve (they are not supposed to they where using what ever they want) the spec even warns about using it for an EOTF:
https://www.itu.int/dms_pubrec/itu-r...6-I!!PDF-E.pdf
In typical production practice the encoding function of image sources is adjusted so that the final picture has the
desired look, as viewed on a reference monitor having the reference decoding function of Recommendation
ITU-R BT.1886, in the reference viewing environment defined in Recommendation ITU-R BT.2035.


it's an encoding function anyway not a decoding function like gamma 2.2.
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Old 17th April 2024, 04:14   #64682  |  Link
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Let me give you a solid example huhn.

https://ibb.co/NV3DcNG
https://ibb.co/dLfQLdh

This frame from the outlaw star bluray. My display is calibrated for 2.4 pure power. I've tried 2.2 pure, 2.1, but the entire bluray series has tons of crush.

UNTIL you either use srgb, or the bt709/601 gamma option. Then the details on the pipes just pop right out. Viewing the image in madvr, press play, or else the gamma function won't shift during pause.

I've tried this on all my LCDs calibrated to pur 2.4, none of them look right. ALOT of older blurays exhibit this problem. I think this is what someone posted about a long time ago on this forum, green crush, where pure 2.4 is NOT the intended target curve of older grades?
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Old 17th April 2024, 09:44   #64683  |  Link
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i can only check with an ycbcr file.

this looks like wrong levels old anime doesn't have a perfect black in the first place. i'm not blaming you for the wrong levels. levels in master is not that rare.
try the newest beta and press control+shift+alt+print
there should be a video screenshot on the desktop RawScreenshots.
you also need ffmpeg in the madVR folder.

just to be clear relative 2.4 or absolutely?

here is sRGB:
https://drive.google.com/file/d/1360...ew?usp=sharing
there is a chance it is used.

green should be the issue the difference between gamma and sRGB is linear in terms of color.
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Old 17th April 2024, 15:03   #64684  |  Link
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Huhn, I'm not disputing that bt1886 2.4 "is" the standard, and is "most probably" the correct default.

My point of discussion here is that "where-ever" the mismatch occurred, mastering-hardware, colorist, compressionist, etc, such "mis-matches" are so incredibly common among the published material, that, it may be likely for these odd-curves to line up serendipitously as the correct display offset on our end^?

The screen shot is accurate as far as demonstrating the effect I'm talking about, it's from an untouched file. I'll look into this new beta, still on 113.

But can you take a look at the dark values, the difference between the shadow detail is rgb 0.1.1 and 3.5.4. That is barely anything. On purepower 2.4, you can not see that difference as detail, especially if the APL of the scene is enough to triggers your eyes to shutter.

Is it not crushed on your calibrated setup?
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Old 17th April 2024, 22:38   #64685  |  Link
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i don't know i don't have the ycbcr image.

the RGB are very close to be dead on my oled on my LCD screen it is fine.
i have relative not absolute gamma on the LCD.

on at 1000 CR bt 1886 should elevate the black even more then sRGB.

and if they are from a BD then they are remastered to the standard used at the time the BD is released.

i would just old something like the sRGB 3d LUT i would clearly not use bt 709. sRGB is an actually used spec.

with a ycbcr file i may have a better idea what is actually happening. maybe this is far from a guarantee.
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Old 18th April 2024, 16:51   #64686  |  Link
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The secret of gamma has always carried with it a mystery. We must learn its riddle. We must learn its discipline.
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Old 18th April 2024, 21:25   #64687  |  Link
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I don't have any 1000cr lcds up and running at the moment, on my crt and oled, the shadow detail is completely crushed as you say. rgb 111 and 555 are less than 0.01 nits @ 120 nit peak sdr. Unless shadow detail is brought up to around 0.03-0.05 nits, you almost can't see it unless the scene APL is very low with almost no bright elements. I'd say it's a challenge to even see 0.05, if there were brighter scenes immediately before the dark scene, you'll miss the detail completely. 5% rgb 131313, 0.1 nit, is imho the cut off for immediately obvious, it's shadow it's detail.

3 possible scenarios. #1, the colorist messed up. #2, they were trying to hide grain shimmer of dark areas. #3 they deliberately wanted an over the top contrast look.

#4, they used a CRT. Maybe even IPS, although, I don't if that was a thing for pros.
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Old 18th April 2024, 21:29   #64688  |  Link
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Quote:
Originally Posted by Siso View Post
The secret of gamma has always carried with it a mystery. We must learn its riddle. We must learn its discipline.
well put Siso, I suspect they just had some intern guy take a swing, although this was a pretty big deal show to remaster for the fans.

Do you think they remastered on CRT 2013-2015ish ?
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Old Yesterday, 10:28   #64689  |  Link
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Maybe on lcd, who knows...
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Old Today, 00:13   #64690  |  Link
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Quote:
Originally Posted by Siso View Post
Maybe on lcd, who knows...
They did that on 2013 ipses?
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Old Today, 01:44   #64691  |  Link
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It's going to get to the point that we're going to need a wheel dial to adjust the gamma and turn it every time to compensate for bad grading.

I sort-of have one, though not in the same sense. What I ended up doing was I set the monitor gamma, then I set a compensation level a little higher (because it's not calibrated but I can see by eye it needs just a little bit more adjustment). So this sets the baseline that is decent. I have bias lighting (wall sconces behind the screen and a dim lamp to the side), so if it's the evening, I will start the show, then adjust the lighting in the room to a level that makes the colours and blacks snap-in more well-defined. You have to adjust the dimmer reasonably quickly, because the eye adjusts fast.
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Old Today, 02:54   #64692  |  Link
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I use the source black level option alot. You got 255 rgb values, +5 is typically enough to bring out most crush, 5 is only about 1.5%. At least with madvr, you can do this without making the black bars worse since they can crop and not be part of the image.

I also suspect they might be using a black floor instead of true blacks to account for the behaviors of consumer LCDs.
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