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[BartMan01]

Trying to calibrate my new projector and am having color space issues with MC.  No matter what I do, I can't get both accurate color space and BTB/WTW info passed to the display.  I have tried setting everything to 16-235 (both YCbCr and RGB) and 0-255 (matched between video card settings and projector settings) and both 'work' as in I get the right color space without banding issues in a gray scale ramp video from MC but no BTB/WTW info passed (it all clips at video black and video white).

In the madVR configuration there is a setting for display color space:
Set at 0-255 (default), everything is good color space (no matter what color space I am actually using) wise but no BTB/WTW. 
Set at 16-235 then everything gets washed out (like you are sending 16-235 to a 0-255 display) regardless of actual color space in use, and BTB/WTW are passed.
Pretty sure from what I have read this is due to the MC configuration of the LAV filters being set at 0-255.

Since MC on the HTPC is my primary video source, I am trying to calibrate everything around that - but it is next to impossible to accurately set brightness and contrast if you cant see BTB/WTW to get that point right when they blend with video black and video white.

Is it possible to configure the MC video path to both be accurate in color space and pass BTB/WTW?

[Hendrik]

LAV Filter configuration has nothing to do with this.

In any case, you don't need BTB or WTW to calibrate your display.

Just get some level test pattern, and calibrate so that when 16 is black and 235 is white, you can just barely see 17 and 234 (brightness as low as possible while still seeing the distinction, and contrast as high as possible, without 234 also blending into full white)
You're not supposed to see BTB or WTW, so you also don't need them for calibrating.

But since you will be insisting that you need BTB and WTW, you also need to set your TV to expect 16-235 if you set madVR to output it, otherwise it'll obviously be wrong/washed out.

[BartMan01]

If the LAV filter setting at 0-255 is irrelevent, then I am totally confused as to why the color space setting in madVR is not doing anything correctly (0-255 always right, 16-235 always wrong).

As to BTB/WTW, I know you can't see them on a properly calibrated display but a properly set up video path will still pass them if they exist in the source.  Right now MC is clipping them, and that is not ideal.  Also there is a range of brightness between when 15-16 become one and 16-17 become one (same on the contrast side and white) and I would rather set the limits to the far point (15/16, 235/236) as opposed to the inner point (16/17, 234/235).

Edit:  my other concern is that if I can't see WTW/BTB that is present in the source, then somewhere in the chain that data is getting truncated.  There are several related parts in the PC video chain and it is possible to set things up so that unwanted conversions from 16-235 to 0-255 and back are going on.  One of the red flags that this is happening is the loss of WTW/BTB information.

[Hendrik]

In fact its the other way around. PCs always operate in 0-255, which does not include BTB or WTW (if black is already at 0, where can BTB be?)
If you try to force your PC to output 16-235 to make room for BTB and WTW, there usually are conversions back and forth, because internally Windows deals in 0-255, and your GPU then converts this to 16-235. This may manage to preserve BTB/WTW with madVR, but it will cause extra conversions.

The straigh-forward way without extra conversion is to simply output 0-255 in madVR, and 0-255 in Windows, and configure your TV to accept that. No extra conversions.
There are some other arguments for 0-255 as well, for example, 0-255 are 256 possible values for your colors, 16-235 are only 220 possible values, so less space for the same image. It may not be much, but it can avoid the occasional rounding error.

If you truely insist on your ways, the best solution is to set windows to 0-255, and set madVR to 16-235, thats the only way to really preserve out-of-range values. If it looks wrong, then your TV is actually properly calibrated for 0-255, and not 16-235.


In any case, anyone experienced with calibrating TVs for HTPCs will tell you that using full-range is the best course of action IF your tv can accept full-range content (some can't), but do as you wish, its your TV. :p

[BartMan01]

Thanks, that helps some.  There is a lot of confusion and conflicting information out there, so that isn't helping me.  I think just for sanity's sake (and due to the lack of known calibrated video source) I will calibrate the display from the PS3 since it will pass the BTB/WTW information.

Current plan would be:
Set all video sources (HTPC, XBox, PS3) to full range 0-255.  Calibrate the set using the PS3 as the video source and then confirm that the HTPC output is 'correct' without funky white space issues like crushed blacks or washed out image.

Edit:
Beginning to think my issues are with something in the video chain that isn't really set the way I think it is.  Falling back to the PS3 for my baseline calibration will help clear this up since there is only the one set of settings I have to worry about.  Too many moving parts on the PC to be confident I have them all set the way I want until I have a baseline to go by.

[felix2]

I use MC as principal video player, output goes to my Yamaha AV receiver, then to the big screen.

I also had significant difficulty getting video calibrated. To cut the story short, I found that the 3 components that determine video are: 1) the video card/controlling software in your PC, 2) the color space of the source video, and 3) the TV color setup.

Most critical is proper setup of the video card control software. For me, it's AMD VISION Engine Control Center for my Radeon HD card. Note that for AMD VISION, calibration for graphics output and video output are completely different. That include color, contrast and color space. You must calibrate using a graphics source (such as you Windows desktop image), then a video source under Video. Note also, for video source, there are 3 basic kinds. Video files (and their many formats), DVD and BD discs. BD video uses its own special color space, different from DVD (which is why BD looks so much better).

It is best to first calibrate the TV separate from the PC. But note also the usual TV sources such as cable, satellite and over-the-air video all may use different color spaces and contrast. So that while the TV is calibrated for these sources, once you use it for PC and its vast varieties of video playback, it will not look optimal. This is all due to many kinds of color spaces used by all such sources (BD being the widest and most demanding). For example, BD demands full 0-255, while no TV sources can come close to delivering such wide dynamic range. So if you narrow the range to get the best TV, your BD playback will be blow out.

There is no one rule to get everything work optimally. One simply has to spent time to adjust and find the optimal parameters for the TV and PC in question.