View Full Version : Difference Recording to Tape and CF


Clemens Fischer
April 4th, 2008, 09:53 AM
made a test today.. recorded HDV footage simultaneous to tape and compact flash unit.

putting the same footage in one timeline results in different lenght of the clips
the compact flash unit stores about 1 second less than the tape shows.

it's not the problem to have 1 second less on card, but that means, that it's not possible to restore a project, which was captured from card when capturing it by tape later.. so all the importet CF footage has to be stored on harddisk to be shure to edit it in the future.

no more restoring with project files possible...

has anyone else tested that?

regards,
clemens fischer

Keith Forman
April 4th, 2008, 10:03 AM
How long was the clip? Was the missing second at the begging or end of the clip or did it have drop outs throughout?

kdbf

Laurence Kingston
April 4th, 2008, 10:11 AM
I have noticed that the video recording on the CF card starts more quickly than it does on the tape. I have also noticed that the red light on the CF unit is still blinking after the tape transport has stopped.

I believe that this is probably why the recommended Sony CF cards are so much faster than the minimum spec speed of 133x.

I don't know that there is any way that this could really be designed better though. I certainly don't want the record to CF delayed to match what is going to tape.

As a documentary guy, I am not so much worried about a perfect match for the CF and tape recorded clips timing wise. I just sleep better knowing that in the worst case scenario (which does happen every so often) I have a backup to that interview that was so incredibly hard to arrange!

Clemens Fischer
April 4th, 2008, 11:06 AM
I have noticed that the video recording on the CF card starts more quickly than it does on the tape.

are you sure? in all my tests there was more footage on tape than on CF. and i tested it with sony and sandisk cards.

I don't know that there is any way that this could really be designed better though. I certainly don't want the record to CF delayed to match what is going to tape.

yes.. it's a great thing. but as i wrote.. if you have to cleanup your harddisk, it's not possible to reactivate a finished project.

Mike Paterson
April 4th, 2008, 11:21 AM
To clarify: Do you mean that the footage recorded to card has a different timecode to that recorded to tape?

Bruce Ostrout
April 4th, 2008, 11:37 AM
HDV is not frame accurate anyway, so you cannot really do a restore from tape as what you recapture is likely to be off by several frames. The best backup is to always have your project files backed up on a 2nd or 3rd hard drive

Gary Nattrass
April 11th, 2008, 03:15 AM
1: I suspect that the extra 1 sec on the tape is to allow the tape to run up to speed.

2: The CF will continue to flash after recording stops because it will still be dumping data from the memory buffer to the card.

Arnaud Keil
April 11th, 2008, 08:24 AM
To clarify: Do you mean that the footage recorded to card has a different timecode to that recorded to tape?

A same shot has'nt got the same TC on tape and on the CF, using Sandisk X133 16Go, for example.