Hello,

In order to do proper calibration, I would like to know if my pc outputs full or limited range rgb. It is a asrock ion 330 with nvidia ion graphics outputting via hdmi.

Thanks !
Fred

Hello,

In order to do proper calibration, I would like to know if my pc outputs full or limited range rgb. It is a asrock ion 330 with nvidia ion graphics outputting via hdmi.

Thanks !
Fred

PC video cards generally output RGB signal (with DVI or D-sub connection) in the 0-255 range with a PC monitor.

However, there could be options in the graphic card properties so that it can output RGB signal in the 16-235 range (range compression from 0-255 to 16-235) when connceted to a TV that cannot handle the RGB signal in the 0-255 range. There could also be options to output in Y/Cb/Cr or Y/Pb/Pr instead of RGB.

For proper calibration (to choose the proper RGB signal range), it depends on the media you want to watch (PC games, DVD/Blu-ray, etc.), the display (PC monitor, TV) and the connection (DVI D/I, D-sub, HDMI).

PC video cards generally output RGB signal (with DVI or D-sub connection) in the 0-255 range with a PC monitor.

However, there could be options in the graphic card properties so that it can output RGB signal in the 16-235 range (range compression from 0-255 to 16-235) when connceted to a TV that cannot handle the RGB signal in the 0-255 range. There could also be options to output in Y/Cb/Cr or Y/Pb/Pr instead of RGB.

For proper calibration (to choose the proper RGB signal range), it depends on the media you want to watch (PC games, DVD/Blu-ray, etc.), the display (PC monitor, TV) and the connection (DVI D/I, D-sub, HDMI).

Nvidia doesn't even give you an option.

If you are using HDMI, they just automatically irreversibly and invisibly compress your output to 16-235.

This means if you are preserving the level on video content video black(16) is now getting out put at 30. So you have to go back and expand the video to the desktop.

The NV control panel doesn't show this, so you'd have no idea it's doing this unless you spend sometime trouble shooting it and measuring patterns back and forth.

Also, this doesn't happen on XP.


OTOH to do a good calibration, for windows + video, it should be as simple as expanding the level to desktop and simple calibrating whatever the desktop levels are.

Thanks for those replies.

I'm indeed using XP.

The nvidia control panel has only two desktop output color options : RGB and YCC444.

The color range can be chosen but only in the video overlay options.

So what should I choose please ?

I have a video projector with both limited and full range RGB options.

I'd just stick with RGB.

You will be outputting 0-255.

So you have two options.

1) If this is a pure media machine, go into the nvidia levels and force 16-235 for video content. Then you can use your projector in limited RGB and you'll get BTB and WTW so you can use a pluge pattern to calibrate with.

2) if this is a media/gaming/browsing machine then expand the levels to 0-255. this will clip off BTB and WTW , but video black will mactch desktop black. Make sure to set your projector to full range RGB if you choose this option.

I'm using a HTPC (Vista) with a nVidia 9600GT into a Samsung LN40B750. If I set the desktop to YCC444, I get ~10 fL increase over what RGB measures (i1) at a 100% amplitude white window pattern. The HDMI Black Level on the Samsung is set correctly for both.

What causes the change in fL between RGB and YCC444?

I'm using a HTPC (Vista) with a nVidia 9600GT into a Samsung LN40B750. If I set the desktop to YCC444, I get ~10 fL increase over what RGB measures (i1) at a 100% amplitude white window pattern. The HDMI Black Level on the Samsung is set correctly for both.

What causes the change in fL between RGB and YCC444?

Some TV's handle data differently

If you initially calibrated with RGB, it maybe using a different brightness map for YCbCr. The Set may be expecting RGB data to be full range and YCbCr data to be limited to 16-235, so at the display it's got an internal setting(possibly accessible in the service menu) that is essentially turning up the contrast.

Nvidia is pretty wonky about consistency with what comes out of their cards though, so my nvidia experiences (8600GTS w/ DVI->HDMI w/o audio and a 8200 motherboard with HDMI w/ audio) may not match what you see, so the best thing would be to triple check with another verifible source.

I got my answer from nvidia. Looks like I'll stick to it for the moment.

"Hello Fred,

Thank you for contacting NVIDIA Customer Care.

This is Matiuj and I will be assisting you with your query. I understand from your email that you would like to know output through HDMI, the RGB signal is full (0-255) or limited (16-235).

It is full (0-255) when outputting desktop through HDMI.

Please feel free to contact us, if you have any further questions."

I got my answer from nvidia. Looks like I'll stick to it for the moment.

"Hello Fred,

Thank you for contacting NVIDIA Customer Care.

This is Matiuj and I will be assisting you with your query. I understand from your email that you would like to know output through HDMI, the RGB signal is full (0-255) or limited (16-235).

It is full (0-255) when outputting desktop through HDMI.

Please feel free to contact us, if you have any further questions."

I honestly dont' think the engineers at nvidia know what they are talking about. I certainly wouldn't put any faith in Matiuj

My 7900 with latest drivers has an option for 16-235 color in the video settings section.

This setting only affects video content, including full screen video.

OP: Do this to properly adjust your PC to TV picture.

1- Set HDMI output to RGB
2- Adjust TV black and white levels FOR YOUR PC DESKTOP PICTURE using these:
http://www.lagom.nl/lcd-test/black.php
http://www.lagom.nl/lcd-test/white.php

3- Calibrate your video source using the video color settings in the nvidia panel (try and get the latest drivers), not the controls on the TV (at least do black and white levels this way)

4- If your drivers have the 16-235 option and you MUST have BTB/WTW simply pick 16-235 and calibrate your video from the nvidia video color settings, you will discover that by adjusting those controls you can get both BTB and WTW.

This way your desktop PC picture and your video PC picture are independent and both correct.


If you want to adjust color properly for your desktop picture you can simply paint a 75% gray area (RGB 190x3) inside a 75% blue area (RGB B190, 0x2) and check it on blue mode/blue filiter.