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Old 19th March 2013, 08:56   #18039  |  Link
truexfan81
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Quote:
Originally Posted by 6233638 View Post
That is completely wrong. There is nothing useful below black or above white. At most there will be specular highlights, which are not detail, and often what you will see is sensor noise/saturation, which should definitely not be visible.
Valid video ranges are 16-235. If you are using the PC for anything other than video playback, it will also give you the perception that video looks dull if you do this, because video white will be at a much lower level than white on the desktop.

In the madVR device properties, output should be set to PC levels (0-255) regardless of what levels your display accepts. What this option does, is fix the video levels to match your desktop output levels. It does this by discarding below black and above white - but that does not contain picture content, and is no longer even necessary for display calibration with flat panels. (only necessary with CRT)

If your display accepts it, you should send it a full range 0-255 signal via HDMI. Most displays will have a "video levels" or "black level" option if they support this - I can't think of anything that automatically switches and does not have a manual override. So if your TV doesn't have the option, it probably doesn't support it.
With Nvidia, the card will output a limited range 16-235 signal when connected via HDMI unless the display explicitly states that it can support a 0-255 signal. My Sony TV does, but it seems that most do not. There is no driver setting for this, but madNvLevelsTweaker.exe inside the madVR folder can force a 0-255 output if your display supports it.

The reason that you want to output 0-255 to the display is because everything on your PC is natively 0-255, and the 16-235 output from the card compresses the levels (rather than clipping them) which can introduce banding, because there are fewer levels of gradation.


Even if you are outputting 16-235 to your display through the graphics card, madVR itself should still be set to 0-255, as this matches the video levels to the desktop levels. As the desktop levels are being compressed to 16-235 in this case, it means that video is contained within the 16-235 range.
and yet it looks better when forced to 16-235
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