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View Full Version : Software Players: RGB TV or Full Level Calibration?


Nullack
25th December 2015, 00:11
Gday Doom9ers and Merry Christmas to all :)

I'm feeding my display RGB on the theory that since GPUs work in RGB I might as well to try and reduce the number of colour conversions / processing in the whole chain. Since film content is largely 8 bit BT 709 YCBCR 4:2:0 or atleast until UHD Bluray comes around, I figured I'd keep my Nvidia setup to RGB 8Bpc.

Then the choice becomes with software players, do you calibrate for TV levels with 16 being black, or PC levels with the full range?

I had a further theory that since there is greater range in 0-255 in PC levels that would be better. But then ofcourse, is the mysterious mention of whiter than white content in some films and blacker than black. I'm not sure if there is in fact any blurays produced with this? And if there is, surely the directors intent was for them not to be visible given the calibration to 16 is black???

Then I added to my theory that while my display is a "TV", its a "smart hub" with a whole bunch of digital content and features; plus my HTPC desktop is a PC. The whole question of what is a TV and what is a monitor has become very blurred in modern times.

I've ran into a practical problem with full range calibration.I need full range PC level 4K UHD test patterns like pluge. Everywhere I look to download some, its all TV levels for calibration.....Then I saw some posts on the AVS Forum claiming PC levels cant be calibrated for. I find that absurd. Surely you still need to eliminate say blooming in calibrating brightness settings. I get they probably just meant brightness and not gamma / colour, but even still brightness can be wrong in PC levels and needs calibration.

So:

* What level do you calibrate too?
* Why do you calibrate to this one and not the other?
* In specific UHD 4K RGB PC Level calibrations, can anyone please share test patterns I can download for calibrating brightness

Thanks

huhn
25th December 2015, 00:57
I had a further theory that since there is greater range in 0-255 in PC levels that would be better. But then ofcourse, is the mysterious mention of whiter than white content in some films and blacker than black. I'm not sure if there is in fact any blurays produced with this? And if there is, surely the directors intent was for them not to be visible given the calibration to 16 is black???

spec is no content has to be there and if there is content than it was a mastering error or should be flagged as full range.

outputting limited ranged doesn't give you any chance to see WTW content.

so you have to output full range with madVR set to limited and ruining your display CR.

I've ran into a practical problem with full range calibration.I need full range PC level 4K UHD test patterns like pluge. Everywhere I look to download some, its all TV levels for calibration.....Then I saw some posts on the AVS Forum claiming PC levels cant be calibrated for. I find that absurd. Surely you still need to eliminate say blooming in calibrating brightness settings. I get they probably just meant brightness and not gamma / colour, but even still brightness can be wrong in PC levels and needs calibration.

there is absolutely no problem to calibrate in full range. there is absolutely no reason for any problems.

I need full range PC level 4K UHD test patterns like pluge.

for what? range doesn't matter. the only thing that matter is how it is rendered.
and what have picture to do with calibration in the first place?

Nullack
25th December 2015, 01:50
there is absolutely no problem to calibrate in full range.....what have picture to do with calibration in the first place?

Thanks mate. I figured the avs forum folk were wrong about that. The reason for pictures is I got hold of some 4K ISF test patterns pictures - I'm in the throws of encoding it into a video via ffmpeg.

For HTPC applications using modern "smart hub connected" displays, do you do TV levels or full levels in RGB? And why?

foxyshadis
25th December 2015, 01:57
WTW and BTB existed in the CRT days. With flat panel, it's all 0-255 in RGB, don't let old broadcast standards trip you up from correctly calibrating your own system, unless you enjoy watching everything washed out.

huhn
25th December 2015, 04:53
For HTPC applications using modern "smart hub connected" displays, do you do TV levels or full levels in RGB? And why?

i use FULL range or more precise a custom range to counter a black issue. full range is more "correct" and my TV can handle it perfectly. there is no reason to let the GPU touch the picture.

i have no clue what "smart hub connected" is.
but a HTPC is working in full range RGB the desktop is "always" treated as full range.