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  1. Hi all,

    This is my first post here. A number of years ago I recorded some old VHS F1 races to DVD. I also copied all of my home videos. Recently I watched some of them and became concerned. I have noticed that all of the recordings I did on my Sony DVD recorder have a small black horizontal line at the top of the screen. If you look closely on the picture below you can see it right across the top of the picture ie. the picture doesn't quite meet the top of the video frame.



    I have noticed that on DVD's sent to me by several people (I collect F1 races converted from VHS) almost without exception they have this black area at the top but it doesn't go all the way along like mine. There is a sort of 'step' where some of the picture meets the top and some of it has the black area like mine. You can see this on the image below from a DVD sent to me:



    Is this to do with de-interlacing? My DVD recorder was definitely sent to record interlaced material when I captured them years ago. What causes this 'step' and why is it absent in my captures? I really hope I haven't done something wrong with my recordings because some of my home movies got damaged in a move and are no longer able to be copied properly so these copies are all I have. Can anyone explain this for me? Cheers.
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  2. I don't know the exact details with PAL video, but with NTSC as an example, the full picture consists of 485 scan lines. The first scan line starts at the middle of the screen, the last scan line ends at the middle of the screen, and there are 484 scan lines in-between. Because computers like regular rectangular arrays those 485 scan lines are capture as 486 lines with the first half of the first scan line, and the second half of the last scan line, black. It has become traditional to capture and save only 480 of the 486 scan lines (to use a mod 16 frame size) -- but different devices start with different scan lines. The situation with PAL video is similar.

    There is nothing to worry about here. Until you started looking at your videos on a computer you never saw the outer ~5% of the frame anyway (because TV's overscan). Think of it this way: you're getting to see more of the picture than you ever did before. So you're gaining something, not losing something.
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  3. Thanks for the reply. One of the guys I trade DVD's with has told me he has a Sony DVD recorder purchased in 2007 (the same year as I got mine) but his is a basic model with no hard drive and mine is a more expensive hard drive version. His Sony has this 'step' and mine doesn't even though they are from the same era and manufacturer which I find odd.

    So based upon what you said this is most likely just a 'feature' of my specific recorder and not a fault or incorrect setting during recording?
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  4. Originally Posted by JonVic View Post
    So based upon what you said this is most likely just a 'feature' of my specific recorder and not a fault or incorrect setting during recording?
    Correct.

    Be sure to go back and read my earlier post again -- I added more information you might have missed.
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  5. Ah yes, I did miss the extra information

    Many thanks for your explanation, good to know nothing is wrong here, I was worried. You have been a great help - cheers.
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  6. Here's a diagram that shows what's going on:
    http://www.ni.com/white-paper/4750/en/#toc6
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  7. If it helps you not to worry about it, here's a screenshot from a "professional" PAL 4:3 DVD. The best of both worlds.
    It's from an old ABC TV series.

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  8. Sorry for the delay replying. Many thanks to all of you for the explanations and examples - very much appreciated
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  9. Is it possible that you only checked US races? I've seen a soft black line instead of a hard half-line in NTSC->PAL DVD releases.
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  10. Member
    Join Date: Feb 2014
    Location: usa
    Search Comp PM
    I see that you trade old F1 races. I also have a very old F1 collection of races I have recorded myself and have obtained via trade. I started recording races in 1983 and I have oringinal broadcasts that go back as far as 1965. If you are interested in trading let me know. Mu email address is sunsplash77@yahoo.com Thanks Larry
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