Do I use RGB or 4.4.4 for 4K TV ?

Subzerok11

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I bought the new Samsung nu8000 and the picture just isn't right. Supposedly if you edit the input to PC the TV will output 0-255. So in my video card settings for my 1060 GTX I have the option of RGB full and 4.4.4 Chroma which one am I supposed to use ?

Second question do I use HDMI black level low or normal ?

I've checked around but I can't get any firm answers to these two questions.
 
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Ocellaris

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Set your Nvidia control panel to output YCrBr color, that will override anything your TV is doing to mess up the colors. That should look “right”.

Then set the Control Panel to RGB full and adjust the black level on your TV so it looks right.
 
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Nenu

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When using ycbcr there are no RGB options (choice is to use ycbcr or RGB, no mix of both).
Instead set to 4:4:4 unless using HDR @ 4K, then use 4:2:2.
 

Kdawg

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when i played with the samsung, I chose rgb full.
There was a bug where i had to pick rgb partial in order for it to display 0-255.

i remember leaving hdmi black normal.
 

Ocellaris

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For RGB on a Samsung TV “Normal" In the TV's menu expects 0-255. “Low” expects RGB 16-235.

In Nvidia Control Panel, Full sends 0-255 and Limited sends 16-235.

So you want Normal on the TV and then Full in the Nvidia Control panel.

Or you just pick YCbCr in Nvidia and you can’t screw it up.
 

Subzerok11

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When using ycbcr there are no RGB options (choice is to use ycbcr or RGB, no mix of both).
Instead set to 4:4:4 unless using HDR @ 4K, then use 4:2:2.
So why do I want 4.4.4 instead of RGB full ?
 

Nenu

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So why do I want 4.4.4 instead of RGB full ?
Ocellaris found that RGB gets messed with more by the TVs he used and you might suffer the same fate.
I'd try both, remembering to calibrate both of them too.
Then see which you think looks best.

If you intend using HDR@4k you need ycbcr 4:2:2.
 

Subzerok11

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Ocellaris found that RGB gets messed with more by the TVs he used and you might suffer the same fate.
I'd try both, remembering to calibrate both of them too.
Then see which you think looks best.

If you intend using HDR@4k you need ycbcr 4:2:2.

When I try to use 4.4.4 it only gives me the limited option, I have to use RGB to get the full mode.
 

Nenu

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The limited option has no effect unless using RGB.
Its only an RGB setting.

Its a hangover for compatibility with older TV and DVD programs (and some older displays) that didnt use the full 0 to 255 range for each colour.
Instead black starts from colour 16 and max brightness is colour 239 when using RGB.
With ycbcr the setting is greyed out and not used.
ycbcr uses 4:2:0, 4:2:2 and 4:4:4 to change its colour compression for bandwidth savings or compatibility.
 

Subzerok11

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The limited option has no effect unless using RGB.
Its only an RGB setting.

Its a hangover for compatibility with older TV and DVD programs (and some older displays) that didnt use the full 0 to 255 range for each colour.
Instead black starts from colour 16 and max brightness is colour 239 when using RGB.
With ycbcr the setting is greyed out and not used.
ycbcr uses 4:2:0, 4:2:2 and 4:4:4 to change its colour compression for bandwidth savings or compatibility.

Oh okay I got it, limited or full is not used with 444 only with RGB, 444 is full. Okay So both options work for me with my setup 444 and RGB FULL does it matter which I pick to use ? from what I've read so far here it seems more people are suggesting to use 444.
 

Nenu

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Oh okay I got it, limited or full is not used with 444 only with RGB, 444 is full. Okay So both options work for me with my setup 444 and RGB FULL does it matter which I pick to use ? from what I've read so far here it seems more people are suggesting to use 444.
I covered it in post 9.
See what works best with your equipment and how you like to view it.
After all, your experience is what matters most to you.

I've played with RGB vs ycbcr a lot and my 1080p projector gives slightly better dark definition with RGB so thats what I use for gaming and films.
But tbh the difference is so small its a nitpick.
I will happily change when I get a new display if it helps.
 

Subzerok11

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Whats odd when using RGB full, the TV will let me adjust HDMI black levels to Normal or Low. But if I set to 444 the TV grays out the Black level option to Normal. Which in the end it don't make a diff cause in FULL or 444 the Normal setting is the correct black level.

Some said that theirs a diff in color tone between the FULL and 444 but I can't tell the diff at all.
 

Nenu

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Depends on the TV and sometimes firmware version.
So many variables its hard to quantify many things as a standard.
 

Armenius

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Whats odd when using RGB full, the TV will let me adjust HDMI black levels to Normal or Low. But if I set to 444 the TV grays out the Black level option to Normal. Which in the end it don't make a diff cause in FULL or 444 the Normal setting is the correct black level.

Some said that theirs a diff in color tone between the FULL and 444 but I can't tell the diff at all.
If you leave the black setting on Auto the TV should properly detect the RGB Full signal and give you the full brightness level. YCbCr is always limited to 16-235 regardless, or 16-240 with "Super White."

YCbCr creates color by dithering the blue and red channels. The 'Y' in YCbCr is a brightness component, while "Cb" and "Cr" are the blue and red color components. It's supposed to look better in video than the static values used by RGB, but in reality it is based on a color format originally created to provide compatibility between color and black and white TV. Visually, there is no difference between YCbCr444 and RGB.
 

Subzerok11

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Quote

"If you leave the black setting on Auto the TV should properly detect the RGB Full signal and give you the full brightness level. YCbCr is always limited to 16-235 regardless, or 16-240 with "Super White."


So your saying YCbCr444 is only 16-235 ? cause that's against what everybody else is saying. But in your last sentence you say "Visually, there is no difference between YCbCr444 and RGB."
 

Nenu

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He is right, I completely forgot ycbcr uses the limited range, age is catching me up.
It explains why RGB full has more dark detail for me.

I think he meant to say there is no difference between YCbCr444 and limited RGB.
Although Armenius often has cool rabbits in his hat, I'm sure his coverage will go further than mine.
 

Subzerok11

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All I want to do is have 0-255 for my PC and for my 4k TV and from what most sources say RGB FULL and YCbCr444 both are FULL range 0-255....correct ?
 

Nenu

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As far as I am aware from my distant learnings and a quick check online, ycbcr (of any type) uses the limited range.
Even 4:4:4 uses the limited range and can be further compressed to 4:2:2 and 4:2:0.
If there are exclusions to this, Armenius is the man to ask. I would wait on his input before deciding.
If he has nothing further to add I suggest using RGB full.
 

Armenius

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He is right, I completely forgot ycbcr uses the limited range, age is catching me up.
It explains why RGB full has more dark detail for me.

I think he meant to say there is no difference between YCbCr444 and limited RGB.
Although Armenius often has cool rabbits in his hat, I'm sure his coverage will go further than mine.
So long as the attached display is correctly resolving the black level then you won't be able to tell the difference most of the time. You'll lose some detail in the darkest black gradients compared to RGB Full, but that is about it.
As far as I am aware from my distant learnings and a quick check online, ycbcr (of any type) uses the limited range.
Even 4:4:4 uses the limited range and can be further compressed to 4:2:2 and 4:2:0.
If there are exclusions to this, Armenius is the man to ask. I would wait on his input before deciding.
If he has nothing further to add I suggest using RGB full.
YCbCr is always 16-235 or 16-240. The reason is all digital display panels are RGB, so the luminance and chroma values have to be converted. In reality, luminance is a percentage value from 0 to 1, while chroma is a deviation value from -0.5 to +0.5. The chroma components in RGB are integers including 0 to 255 (or higher, depending on bpp). The equation responsible for conversion into the RGB color space requires scaling and rounding, otherwise the brightest and darkest values can be clipped or crushed when the final image is displayed.

Bottom line is, for PC usage, always use RGB Full.
 

Meeho

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Always send RGB to your TV if you can. This avoids unnecessay conversions or possibly wrong conversions between color spaces. 0-255 too if your TV doesn't introduce errors like banding or similar with it. Also check if your TV has a 4:4:4 mode setting and use that.
 

Commander Shepard

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If I set Nvidia Control to RGB Full and leave my Samsung HDMI Black Level at Normal the screen looks the same as when Nvidia is set to YCbCr444. If I set the HDMI Black Level to Low or Auto, everything is a few shades darker.
 

Subzerok11

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So long as the attached display is correctly resolving the black level then you won't be able to tell the difference most of the time. You'll lose some detail in the darkest black gradients compared to RGB Full, but that is about it.

YCbCr is always 16-235 or 16-240. The reason is all digital display panels are RGB, so the luminance and chroma values have to be converted. In reality, luminance is a percentage value from 0 to 1, while chroma is a deviation value from -0.5 to +0.5. The chroma components in RGB are integers including 0 to 255 (or higher, depending on bpp). The equation responsible for conversion into the RGB color space requires scaling and rounding, otherwise the brightest and darkest values can be clipped or crushed when the final image is displayed.

Bottom line is, for PC usage, always use RGB Full.

Well okay then I'll just use RGB FULL with HDMI black level at normal with my 4k TV then. It's done thanks everybody.
 

Fahrenheit

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Just like to add that the blackest black is the same for both 0-255 and 16-235 (0 or 16 respectively).
 
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