Proper VirtualDub video levels for Tevion USB capture?
I know it may vary depending on my equipment. I am using Windows 10 64bit. My video source is VHS. I have figured out the default options (after having to install the device on another computer). My settings are set to the defaults and they are the following:
Brightness 128 Contrast 32 Hue 64 Saturation 32 Sharpness 2 I've read that sharpening VHS is a bad idea. So I am thinking sharpness should be 0. As far as brightness, it seems a little too bright, so I have lowered it to 100, but I am not sure if that is correct. My previous setup (same equipment) I had these settings: Brightness 100 Contrast 34 Hue 74 Saturation 34 Sharpness 2 I'm honestly not sure how to properly calibrate these settings. I know I'd likely be calibrating them for my monitor and I am concerned exactly what settings I should use. I think the brightness should be lowered as I was told "the levels need to be lowered to 100 in VirtualDub when the time comes," but I really don't know which levels this meant. The brightness is definitely too high at 128 because black almost looks like gray. Should I focus on trying to set the brightness where I am setting black to be a black as possible without going too far? What is the best strategy for the other settings? Should I keep a little sharpness? Should I change my Hue/Contrast/Saturation at all? |
100 is correct. That's what "levels" meant when that was written.
Video does appear slightly darker on a computer than on a TV. And that's another reason you encode a copy for streaming, and leave the original unmolested in an interlaced archive version. If it's too bright on a computer, it's ll REALLY bright on TV. Everything else was fine at default. Sharpness at 2 or 0 makes almost no difference. This is an Empia chipset like the ATI 600 USB. The reasoning for the sharpness applied is that the chroma in Empia cards isn't quite as crisp as you see in some higher-end (are harder to install) cards. But for VHS, it's not really going to be a huge issue, because the resolution is lower than the chrominance anyway. I turn mine off, 0 setting. |
Ok awesome. I'll set brightness to 100 and sharpness to 0 and call it a day. Thank you!
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The measured "y" values are luminance values. Use the VirtualDub capture histogram to set incoming levels to stay within the proper digital video range of y=16-235. "Y" levels will vary during play, but you don't want them to exceed 16-235, so play a short segment of tape to check how levels look in general, then start the capture after tweaking your settings. Note that black borders coming from the signal are usually belong at y=0 black, so temporarily crop the borders when taking your readings. Black borders would appear as a small sharp "spike" at the left=hand border of a histogram. This has all been covered in the detailed VirtualDub capture settings guide: Quote:
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Do you know what Contrast does? It controls the brightest values and specular highlights of the image, while brightness controls black levels. Adjusting one can slightly affect the other, so you often have to jockey back and forth between Brightness and Contrast to get things settled. It gets to be second nature after a brief trial period. Use the histogram -- that's why the histogram is there, it's not just a gimmick to decorate the interface. :wink2: A badly oversaturated signal causes color bleeding, especially with reds. This is a touchy subject. Changing saturation doesn't affect one color, it affects all colors. You could end up with pretty reds in an otherwise gray image. Does that sound OK? You have better control over this sort of thing in post processing, where you can modify the saturation of individual colors and also control bleeding and chroma shift. If you're working with video using an uncalibrated monitor, you're making life really tough on yourself. |
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