15fps ?

[Dwight]

How could I recognize if a tape I have is recorded with a camera that only recorded at 15 fps ? (yes, bizarre question)

Old home videos from the early 90's tend to drop frames 10/second so that's why I'm asking this. Pro shot videos naturally do not drop at all

[Dwight]

anyone ?

[chazzie]

It's due to the Timecoding sequence, old VHS-tapes do not have a correct audio/video timecode. There are timecode converters availible, but I don't know where you can pick one up.

Chazzie

[Dwight]

Thanks for the response.
Never heard of that Timecode before.
Now if anyone knows how to get past this problem and get the videos captured

[Craig Tucker]

Are you using the same method of capture for both videos ? those that do and don't drop frames

[Dwight]

Well..yes..both with Virtualdub

[Craig Tucker]

The reason I asked is that vdub default capture framerate is 15fps, if you dont change it you will drop the remaining frames. Is it possible you forgot to set the correct capture framerate ?

[Dwight]

Nope, not possible. I always try to capture at 25 fps since I'm from the PAL region myself.

[kees1952]

I've never heard of VHS recording other then 25 fps (PAL). This depends on the fixed rotation speed of the video head(s).
The reason why you are dropping frames with these old tapes is probably the bad condition of the (frame)sync pulses in the video signal. Try to put the video signal from the VHS recorder on an oscilloscoop and compare the signal from the old tapes to a recently recorded one and try to see the difference. If there is a big difference this can only be handled by adding some electronics before feeding the signal to the capture card.

Regards, Kees Janssen.

[Dwight]

Wish I had an oscilloscope or access to one
Haven't used one since my electronics studies ended a year ago or so.

Actually one of the tapes I tested was not that old..but the material in it was filmed long time ago..so it was a copy of a VERY old tape.

[sammie]

Kees probably has the right idea, although an interesting suggestion on the o-scope. Most of the little copyguard removal boxes also boost/restore the sync signal. Artificially lowering that used to be a copy protection scheme for tapes. But I find the devices work great for old tapes too.

[Dwight]

Apologies for revisiting this OLD thread like this

But the same tapes seem to capture normally when using
DV-capture (camcorder ->firewire) method (does the sync get boost in this then= , now why is this ?
This massive 10 frames/second dropping only seems to be
a problem with tv-card capture. . . . . a shame, still
haven't worked around this one.