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I addressed this in the other thread, but as many people may read this one as well, the answer is yes and no.
Video levels are 16-235, PC Graphics levels are 0-255. That is for reference black to reference white. Note how video levels are not the same as Graphics levels, and how video levels (aka Studio Levels) provides codes for footroom (below black) and headroom (peak whites). Graphics levels do not, as the black and white points are at the extremes.
Video test patterns are coded properly with Video levels, such as Avia or DVE. If you are playing back DVD or other video material through a computer (many people do), you should take care to make sure that video levels are being maintained properly by using newer video cards, up to date drivers, and VMR9 instead of overlay. Otherwise, your PC very well may perform a video levels to graphics level expansion to remap the video 16-235 range to the graphics 0-255 range, thus clipping below blacks and peak whites, and introducing contouring/banding effects. In any case, if video content is properly maintained on your PC, it will NOT match the 0-255 range of graphics content such as video games, your desktop (XP MCE GUI is an exception), images, etc. So, yes you *should* use a dvd such as Avia or DVE to align your video playback on your PC if that is your video source (many people use HTPCs, including myself). However, if you are not using your PC for video playback, and instead using it just as a computer, aligning to video levels would be wrong, and instead you would want to align to PC levels using patterns encoded for such a task, or by using pc calibration applications that you find online, as they should be encoded with patterns where black and white are 0-255 rather than the 16-235 video range of patterns on Avia or DVE.
More discussions are linked in my signature on this issue.
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