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  1. I remember thinking last year when I captured my dv tapes that the captured footage didnt look as nice as what it does on the cameras screen. Sunny days in particular just dont look as bright and sunny as what they do on the cam screen.

    Just wondering if this clip needs any brightness/contrast adjustment? It seems to look ok with the vdub histogram filter.

    I captured this via firewire with scenelyzer. Shouldnt it be an exact copy of the tape? Is it normal to need to adjust levels of dv capture?
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  2. Looks ok to me. Luma 16 ...235 well exploited, same for RGB (0....255). Minor tweaks are a matter of personal preference. Personally I wouldn't do much though.
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    Last edited by Sharc; 27th Jan 2024 at 07:09. Reason: Files added
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  3. Cheers Sharc. It must be my eyes. All of my captures, both dv and vhs all seem to look a little too dark to me, even when the histogram says otherwise.
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  4. You can still tweak as you prefer in postprocessing. Just make sure that you do not drive the brights and darks beyond the legal values, or worse even into the clipping. I just wouldn't change anything for the capturing process as this looks fine.
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    Last edited by Sharc; 27th Jan 2024 at 10:25.
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    Originally Posted by Sharc View Post
    Looks ok to me. Luma 16 ...235 well exploited, same for RGB (0....255). Minor tweaks are a matter of personal preference. Personally I wouldn't do much though.
    Double check that the range is not 16-255. I have never seen a miniDV cassette in a luma range other than 16-255.
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  6. Originally Posted by rgr View Post
    Originally Posted by Sharc View Post
    Looks ok to me. Luma 16 ...235 well exploited, same for RGB (0....255). Minor tweaks are a matter of personal preference. Personally I wouldn't do much though.
    Double check that the range is not 16-255. I have never seen a miniDV cassette in a luma range other than 16-255.
    Whatever cameras and capture gear do, keep in mind that in 8 bit world any luma (Y') value >235 or <16 leads to invalid RGB values (negative or >255) after standard YUV->RGB conversion (limited range YUV -> full range RGB, applicable for broadcast, DVD, Blu-ray, home video .....) for final viewing on your TV/monitor. Means the RGB gets clipped and one looses details in the brights or darks. Harmless, if those excursions happen occasionally only, or are just caused by noise. People are usually not aware of the lost details in the brights and darks though, because what they don't get they don't see and don't miss.

    Topic: "the inner RGB cube in outer YUV (=Y'CbCr) cube", see for example here:
    https://forum.videohelp.com/threads/398289-I-m-having-a-hard-time-understanding-colormatrix

    There is a reason why AviSynth YUV histograms mark these super whites and super blacks with brown bars (sometimes called "headroom" and "footroom"). Anything in there (except noise) just calls for trouble. Fortunately one may not easily notice the defects.
    Last edited by Sharc; 28th Jan 2024 at 04:28. Reason: Typos
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    Originally Posted by Sharc View Post
    Originally Posted by rgr View Post
    Originally Posted by Sharc View Post
    Looks ok to me. Luma 16 ...235 well exploited, same for RGB (0....255). Minor tweaks are a matter of personal preference. Personally I wouldn't do much though.
    Double check that the range is not 16-255. I have never seen a miniDV cassette in a luma range other than 16-255.
    Whatever cameras and capture gear do, keep in mind that in 8 bit world any luma (Y') value >235 or <16 leads to invalid RGB values (negative or >255) after standard YUV->RGB conversion (limited range YUV -> full range RGB
    It's not a problem, you can convert full range YUV -> full range RGB. Or change the range 16-255 to 16-235 earlier.

    And in the case of miniDV cassettes, you even have to do this. But the attached sample is too short -- you need a section with very bright areas.
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