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  1. Since the slider is in the middle by default, if I set the sharpening to zero, will it blur the source video? Also, I shouldn't have to mess with the brightness slider because I am going to keep it at YUV. I can always bring down the white point later.

    https://forum.videohelp.com/threads/348981-Overblown-whites-when-capturing-Betamax-tapes#post2184717
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  2. Originally Posted by Hypersonic1 View Post
    Since the slider is in the middle by default, if I set the sharpening to zero, will it blur the source video?
    It depends on the capture device. With some "0" is no added sharpening. With others the middle is no sharpening, the left is blurring, the right is sharpening.

    Originally Posted by Hypersonic1 View Post
    Also, I shouldn't have to mess with the brightness slider because I am going to keep it at YUV. I can always bring down the white point later.
    You won't be able to recover darks and brights if your cap has totally crushed blacks (ie, Y would have been less than 0) or totally blown out whites (Y would have been greater than 255).
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  3. It depends on the capture device. With some "0" is no added sharpening. With others the middle is no sharpening, the left is blurring, the right is sharpening.
    Diamond VC500.

    You won't be able to recover darks and brights if your cap has totally crushed blacks (ie, Y would have been less than 0) or totally blown out whites (Y would have been greater than 255).
    How would I know? What is the maximum brightness value stored on a Video8 or VHS?
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    It doesn't work that way. You have to judge your levels by eye, for the most part. The only things that should be pure white are specular highlights and light sources, ideally. So if you have areas that are white blobs, turn down the gain until they show some detail. If they just turn into gray blobs, then the recording is clipped and there's nothing you can do. (It's also possible the VCR output is too hot, but that is a tech adjustment inside the cabinet.)
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  5. Originally Posted by Hypersonic1 View Post
    You won't be able to recover darks and brights if your cap has totally crushed blacks (ie, Y would have been less than 0) or totally blown out whites (Y would have been greater than 255).
    How would I know?
    The best way is to use a waveform monitor or a histogram.

    Originally Posted by Hypersonic1 View Post
    What is the maximum brightness value stored on a Video8 or VHS?
    Video8 and VHS are analog, not digital. You get whatever digital values your capture device converts those analog levels to.
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  6. Video8 and VHS are analog, not digital. You get whatever digital values your capture device converts those analog levels to.
    Regardless, there must be some sort of a limit. Anyway, the histogram in VirtualDub just shows black at the bottom. It's completely useless.
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  7. Originally Posted by Hypersonic1 View Post
    Video8 and VHS are analog, not digital. You get whatever digital values your capture device converts those analog levels to.
    Regardless, there must be some sort of a limit.
    Unless you're designing your own video devices it doesn't matter to you. Whether it's 1 V or 1000 volts the numbers you get from the capture device will range from 0 to 255. Full black is defined as 16, full white as 235. As long as darks aren't crushed at 0 and brights aren't clipped at 255 you can adjust the picture to be withing the 16-235 range after capturing.

    By the way, it's 1.0 volt peak-to-peak, from the bottom of the sync pulse to peak luma.

    https://www.maximintegrated.com/en/app-notes/index.mvp/id/1184
    http://www.ni.com/white-paper/4750/en/
    Last edited by jagabo; 3rd Dec 2017 at 23:01.
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