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How could I calibrate for 0-255? Are there any calibration patterns for it?

post #1 of 101
Thread Starter 
hello guys, I'm new on AVS, great forum.

My question is regarding the PS3s RGB Full range which is what I've heard is 0-255. Are there any calibration patterns created at 0-255? Or can you use any patterns for this?

Now I also have the two main Bluray calibration discs as well, Spears & Munsill and DVE HD Basics. I'm unsure if I should use these for RGB as I think there created at YCBCR and may get the wrong results, even if I set the PS3 to output RGB for video. As Games are in 4:4:4 arn't they?
post #2 of 101
I have a set for sRGB already, or I can generate a set for you at a certain gamma level. Which would you prefer?
post #3 of 101
Thread Starter 
That is very kind of you thanks a lot. I believe the best gamma level would be 2.2.
post #4 of 101
The question is actually with the display.
Via EDID the display will tell the HDMI source what image level it expects regardless of the capabilities of the source, and the source will re-scale its output as required.

As for calibration images see: www.lightillusion.com/registration_calimages.html

Steve
post #5 of 101
Thread Starter 
Your link doesn't seem to work on my iPad. Says your bandwidth is exceeded.
post #6 of 101
Yep - just noticed that...
Fixing now. Give it half an hour smile.gif
post #7 of 101
Thread Starter 

Thanks guys for the images.

I have another question. If I'm playing a Video Game that was created at 0-255 ( RGB Full Range) but my TV only supported the Limited range, should I calibrate using something made in the limited range like DVE or should I calibrate to the games PC levels even though my TV don't support it.

My PS3 is always set at the Limited Range by the way.
post #8 of 101
Please see my comment about EDID and HDMI.

The whole idea about HDMI and EDID is the the output is always rescaled to the expectations of the display.

But, it would be interesting to know if this fails... does the source not always follow the display requirements?

I know some of the HDMI boxes do not work as expected - they do not communicate correctly - but is this true of games consoles, etc?

Just wondering...


Edited to say:

If your console is always set to 'limited' (TV Legal in the professional world) then the rescaling is on by default, so there is nothing more you can do...
post #9 of 101
Thread Starter 
So what your saying is don't bother with trying to calibrate to the Video Games levels, you should always calibrate to what your tv is expecting?
post #10 of 101
Basically, yes - assuming the EDID is working correctly.
If it isn't, you need to find a way to manually match the image output from the PC/games console to the display's input levels.
Without this match nothing will calibrate correctly.

Steve
post #11 of 101
Thread Starter 
Hi again. I'm unsure about what I said in my first post really about the calibration discs like DVE or Spears & Munsil being in YCBCR. Are these discs generally only for content created in the ycrcb color space? Could I set my PS3 to output RGB for this or would I get odd results if I did that?
post #12 of 101
No simple answer to that...
If the display expects TV Legal range (16-235) the outputting RGB at 0-255 will cause image clipping.
But, the EDID may override you settings and force the RGB output to 16-235 levels, and even force it to YCrCb.
The only way is to test...
HDMI communication can a bit of a black art.
post #13 of 101
Thread Starter 
Thanks.

My question regarded just outputting RGB in the limited range as my TV only supports that. If I wanted to setup my TV for games with a disc like DVE, and instead of setting the color output to ycrcb but RGB, would I get odd results or incorrect results if I did that?

Oh and something else just to be sure. Those test pattern on the site you gave me. Are they for RGB? or YCBCR? Or both? And are they for the limited range or the full range?
post #14 of 101
Sorry to say I think you are missing the workflow that will actually take place.

The display, via EDID, will tell the source what it expects.
The source device will set it's output to that the display expects, and that includes colour space and levels.

The CalImages on the Light Illusion website have been made in RGB data, with a range of 0-1023.
But, they will be 'output' via the HDMI port of any system based on the display's EDID data settings.
So, converted to YCrCb, and 64-904 range as required.

See: http://www.lightillusion.com/idiots_guide.html for more info on this.

If the display can be set to expect RGB input (as with default PC displays) the output will be set to match.
If using a home TV it depends on the TV...
Can it be set to expect RGB input or, as with most home TVs, will it expect YCrCb only?

Hope this helps.

Steve
post #15 of 101
Quote:
Originally Posted by Tyrone Burton View Post

Thanks.
My question regarded just outputting RGB in the limited range as my TV only supports that. If I wanted to setup my TV for games with a disc like DVE, and instead of setting the color output to ycrcb but RGB, would I get odd results or incorrect results if I did that?
Oh and something else just to be sure. Those test pattern on the site you gave me. Are they for RGB? or YCBCR? Or both? And are they for the limited range or the full range?

If you use a disc like AVSHD709 to calibrate, you can use it in either colorspace (RGB or YCbCr) and video or PC levels (16-235 or 0-255). YCbCr is always video levels (16-235) and RGB can be either. On Samsung TVs you can send RGB Full Range (0-255) to the TV and set HDMI Black Level to Normal on the TV and everything will calibrate exactly the same as it would if you were to send RGB Limited Range (16-235) to the TV and set HDMI Black Level to Low on the TV. Also, RGB Limited Range and YCbCr should calibrate the same if your TV can handle both properly, so in a ideal world whether you send RGB or YCbCr to the TV, the end result should be the same.
post #16 of 101
Thread Starter 
It did thank you.
post #17 of 101
Thread Starter 
Quote:
Originally Posted by PlasmaPZ80U View Post

If you use a disc like AVSHD709 to calibrate, you can use it in either colorspace (RGB or YCbCr) and video or PC levels (16-235 or 0-255). YCbCr is always video levels (16-235) and RGB can be either. On Samsung TVs you can send RGB Full Range (0-255) to the TV and set HDMI Black Level to Normal on the TV and everything will calibrate exactly the same as it would if you were to send RGB Limited Range (16-235) to the TV and set HDMI Black Level to Low on the TV. Also, RGB Limited Range and YCbCr should calibrate the same if your TV can handle both properly, so in a ideal world whether you send RGB or YCbCr to the TV, the end result should be the same.

Yes. The HDMI Black Level settings and the ability to set the TV to expect 0-255 is exactly why I chose a Samsung. I havnt got it yet, but with all these handy settings, setting up a TV fir things like games is so much easier.
post #18 of 101
Quote:
Originally Posted by Tyrone Burton View Post

Yes. The HDMI Black Level settings and the ability to set the TV to expect 0-255 is exactly why I chose a Samsung. I havnt got it yet, but with all these handy settings, setting up a TV fir things like games is so much easier.

Ah - in which case the 'difference' you will see with RGB vs. YCrCb will be mainly down to the 4:2:2 signal used with YCrCb.
This tends to give some small colour errors when going between colours that are opposite each other green-magenta for example.
RGB is always 4:4:4.

The variation in data range (0-1023 vs. 64-940) has little impact on the image quality.

Does this help further?

Steve
post #19 of 101
PS3 uses 4:4:4 for YCbCr output
post #20 of 101
Thread Starter 
Yeah thank you.

Just for the record, is there such thing as test patterns in 4:4:4 RGB?

I'll have to use my calibration discs for now, but just wondering if their possible to find.
post #21 of 101
I think test patterns are essentially based off of RGB triplets before being encoded into YCbCr, not sure though.
post #22 of 101
Thread Starter 
Quote:
Originally Posted by PlasmaPZ80U View Post

PS3 uses 4:4:4 for YCbCr output

Does the PS3 do the same for RGB output for video?
post #23 of 101
Quote:
Originally Posted by Tyrone Burton View Post

Does the PS3 do the same for RGB output for video?

like Steve mentioned, RGB is always 4:4:4 (by definition)
post #24 of 101
post #25 of 101
Quote:
Originally Posted by Tyrone Burton View Post

Yeah thank you.
Just for the record, is there such thing as test patterns in 4:4:4 RGB?
I'll have to use my calibration discs for now, but just wondering if their possible to find.

The Light Illusion Cal Images are indeed RGB.
If you set your display to expect input RGB, and feed the Cal Images direct from a PC (making sure no ICC or VCGT are active) the image path will be RGB.

Steve
post #26 of 101
Thread Starter 
Quote:
Originally Posted by Light Illusion View Post

The Light Illusion Cal Images are indeed RGB.
If you set your display to expect input RGB, and feed the Cal Images direct from a PC (making sure no ICC or VCGT are active) the image path will be RGB.
Steve

The best way for me to view these images is on my PS3. which I'm sure will be outputting RGB for it's photo viewer. I'm not sure I can set my TV itself to RGB, only tell the PS3 to output it. Although my TV does have a kind if PC mode setting.
post #27 of 101
Worth trying...
If you do get an RGB connection you will see a slight difference on the BarsAndBlack image between the Green and Magenta patches.
RGB will have a cleaner transition - YCbCr 4:2:2 will have a 'muddy' transition.

Any help?

Steve
post #28 of 101
Thread Starter 
Yes thank you again. I havnt got around to using these patterns yet, but will do it today.
post #29 of 101
Thread Starter 
Hi again, I'm unsure about this. I believe when setting brightness for games I should see all the blocks ect. I remember when I was calibrating my TV for movies on DVE that it said monitors cut all information below black and above White. I think but am unsure, that game developers create their games on monitors? Would that mean that game devs don't use below black or above White? Thus the games have no BB or AW?
post #30 of 101
Games are data range - 0-255.
Video is 16-235.

So, there can be no super black, or super white id a data range image.
(Nothing below 0, or above 255).

Cheers,

Steve
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