eli5; Why do tapes have screen tearing and splitting, but modern media doesn’t?

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I get that TVs have faster refresh rates now but even if you play a dvd on an old tv it doesn’t tear when you pause it. What was so different about vhs tapes that made them freeze mid transition? Cause from what I understand, unlike actual film, which would have mid frame pauses, tape is encoded the exact same way as a disk or even a stream, so why do they buffer instead of tear?

In: Technology

3 Answers

Anonymous 0 Comments

Information on a VHS was an analog signal. To fit all of it on a tape in a linear form would end up with miles of tape. So they record the information in diagonal stripes across the tape, which is much wider than it would need to be if it just held a single track. This is then played back through a spinning head that is place at the same angle relative to the tape as the information on it. The tape moved by the head as the head spins, reading each stripe in a fluid motion, creating the smooth video you see on playback. Pausing it stops the tape moving, but not the spinning head. So the image you see is whatever that spinning head is reading repeated over and over. Hence the stuttery or “between frames” effect.

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