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[TorqW]

Experiencing some problems with my htpc.

Using a  nvidia gtx 760. I've used the registry tweak to output full rgb (0-255) over hdmi.
When calibrating with the HD basics blu-ray I do not see the outer "below black" bars, they seem to be being clipped, no matter what I do to the jriver brightness controls or those on the projector. Have checked madvr and it is set to full rgb.

Strangely, when I use TMT6 there is no problem seeing the full pattern so it can't be a problem with the card or the receiver. This problem is unique to jriver.

Obviously the projector (jvc x500r) is set to enhanced to cope with the full range.

Any suggestions would be very welcome!

Thanks in advance.

[Hendrik]

You're not supposed to see the "below black" bars, since black is supposed to be the darkest color your TV can show. If you can see the "below black", it means that your black is actually grey, and the real black is something which is not commonly used in the videos.

Yes, MC handles it all as designed, and outputs full RGB. You don't get below black or above white, because its not supposed to be shown. Black is the blackest black your TV can show, anything "below" that is also just black.

[TorqW]

Hendrik, firstly thanks very much for your reply. I'm a huge fan of your work and what you've done for the HTPC community, so thank you for that.

I guess I wasn't clear in my question - apologies.

Here's my understanding, please let me know where I've gone wrong:

Full RGB goes above white and below black. The pluge used on the HD basics disc has outer bars that are below black and a background that is at the required black level. The idea being that to get the correct 'brightness' setting you should dial down brightness to the point that the black and below black levels look the same, ie the black outer bars become invisible. So I agree with you that you shouldn't be able to see the below black bars ONCE properly calibrated.

When I perform this test using TMT6 with projector brightness set too high, I can easily see the outer below black bars and dial down the brightness until they disappear just as I do with my standalone blu-ray player.

With JRiver, it appears to clip the below black levels so I can't see the outer below black bars to get the brightness levels correct. Yet MadVR RGB is set to 0-255.

Shouldn't JRiver behave in the same way as TMT6 in its presentation of video material? As I said, it seems to be clipping the signal when other video players (correctly, such as my standalone BD player) don't.

Thanks for your thoughts.

[Hendrik]

Such calibration things don't work with madVR if you output 0-255.
madVR will convert the video level  from 16-235 to 0-255, so that the full spectrum is used for actual content, and there is no 0-16 in the spectrum which is just never used.

If you want to calibrate with this, you should lower the brightness until 16 and 17 look exactly the same, and then increase it one by one until you can see a difference.
Same for white with contrast.

You don't need the 0-15 bars to appear just for calibration.

[TorqW]

Thanks again. Yes that sounds perfectly logical.

Is there a pluge you would recommend to use for this sort of calibration, ie something that differentiates between 16 and 17?

Also, is there a good pluge for contrast too?