Transferring a VHS.

[NY]

Some DVDs of TV programmes made partially on film and partially on video can look really *horrible* on a flat-screen monitor, if the video frame captured digitally for display on the monitor has synchronised with the wrong field.

For film, the video frame *should* be two fields of the *same* film frame, so no movement between them, just added spatial resolution. But if the video frame consists of a field from one film frame and a field from the next frame, then every single combined video frame is blurred, with ghosting. For some reason, this is a lot more noticeable with film than with video where there would still be mixing of two fields taken 1/50 second apart. Maybe it's because the movement is greater: the fields are taken 1/25 rather than

1/50 second apart.

[Dave Plowman (News]

That was once so. but modern telecine machines can run at any speed.

[NY]

Are you saying that the film is run at 24 fps and scanned at 25 fps, without there being any beating?

I thought films were still run at 25 fps, 4% fast. But nowadays the (slightly speeded-up) sound is pitch-shifted downwards by about a semitone to correct for this, so people with perfect pitch no longer complain about it.

[Steve Walker]

They probably don't do it for such a slight difference, but modern technology is surely capable of scanning a 24 fps film, comparing the frames and interpolating to give a true 25 fps where only the first and last frames are identical to the originals?

[Dave Plowman (News]

Think it all started when they fitted telecines with a frame store. And dispensed with a mechanical shutter. Such a beast could be run from a still frame and give a decent picture as it ran up to speed. But it's a bit outside my field. ;-)

[Peter Able]

This all begs the question - why don't the TV stations transmit films at

24fps?

Modern TVs aren't going to melt down, are they?

PA

[NY]

It would seem very sensible to do this - providing all the equipment along the way (including monitoring equipment) and all consumer TVs, PVR etc can handle 24 fps as an alternative to 25 fps. A change from 25 to 24 would be very small, but it might be enough for something to go "computer says NO".