VFR Pulldown Cadence Error

[Ren Hinks]

I just recently captured 10 hours of footage shot on a rented Panasonic DVX-100A and had the same FCP error message (VFR/Pulldown Cadence Error) show up on just about every single tape, usually just one instance every tape but one tape had several spots on it. I say spots because in every case, the problem was exactly at the same point on the tape every try. The only way I found around it was to skip over that small portion of tape.

This really changed my workflow which was geared toward digitizing all the tapes in a short amount of time (the rental was due back). My initial method was to attempt to digitize the entire tape using the “Create New Clip” option to work around the Panasonic generated timecode breaks (there were a TON of those – not anything like working with a SONY 600 BetaCam but I really wanted 24 PA for this project). I ended up taking the time to log and capture to make sure there there was at least a record of offline clips saved to the browser and that when I did run into the error, it didn’t take out a huge clip that I would have to take the time to re-do again, in smaller chunks. I learned the hard way because one of the first times this happened, it not only stopped the process after about 40 minutes of digitizing, it deleted all the new smaller clips that had been created due to the broken timecode AND the clip’s linked QT media as well. I had to start completely over on that tape – not a happy camper at 2 in the morning.

FCP was fine with automating its creation of smaller clips with continuous timecode from broken timecode tapes but was stopped cold with the cadence error. It asked to “continue” or “cancel” as you mentioned but I don’t believe that FCP would do anything more than a “retry” if you clicked “Continue”, not adding any extra processing in an attempt to increase the possibility that the clip would successfully digitize a second time around. Also aggravating was that most times when the error occurred, I also found that FCP had been corrupted and usually had to save my project, exit FCP and restart it to get normal operation back again. I asked the rental house about it when I returned the equipment but they had never personally experienced the problem nor had they heard any other users of the camera report a similar problem.

Your report of the very same problem has me thinking that there is a design weakness in how the Panasonic prints to tape (or a problem with the tape stock itself – I was using the rental house recommended Sony DVM60EXL) as none of my cadence errors occurred at start/stop points – always mid-stream on a shot and not even during unusual physical conditions such as sudden camera movements.

These errors did not show up when I first copied the entire tapes straight into a DVD recorder to show rushes to the producer, so it seems like it has to do with a mis-print to tape that causes the FCP 2:3:3:2 advance pulldown removal algorithm to hit a snag for which there is no “on-error” code to work around the missing frame count or even exit gracefully.

ren

[James Vancouver]

Hey – I’m hoping perhaps you eventually found a solution to this problem? I’m currently experiencing the exact same problem. Strange thing is, I’m re-creating a short film scene by scene from an editor who used these exact tapes before me. Because these errors are popping up in the middle of takes, I can only assume the previous editor did not experience these errors otherwise he would not have been able to capture the clip…now I’m trying to capture the same clips, from the same tapes, and I’m getting these errors. I don’t know what to do. I thought it was a setting thing as I’m relatively new at this, but sounds like it is a timecode thing. Is there a way around it other then capturing around the cadence error (VERY time consuming to figure out its exact spot).

I’m hoping you have an answer…

J