FORUMS: list search recent posts

"Invisible" HDV Footage: Can Only See Footage on Fast Forward

COW Forums : Canon Cameras

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Shawn Romano
"Invisible" HDV Footage: Can Only See Footage on Fast Forward
on Aug 18, 2009 at 1:24:10 pm

Hi. I'm having a very strange problem. I recorded a bunch of mini dv tapes on my HV30 during a trip to the Dominican Republic. All of the tapes capture fine except for one. Here's what's happening:

When I play that tape back, I get a "blank" blue screen with frozen timecode. But when I fast forward the tape, I can see the footage, and the timecode advances. I am capturing from the very same camera the footage was recorded on. Needless to say, I'm baffled.

Any insight on this would be a big help. Thank you.



Return to posts index

Tony Collins
Re: "Invisible" HDV Footage: Can Only See Footage on Fast Forward
on Oct 22, 2009 at 7:18:15 pm

I have same problem with 2 cameras now, and as far as I can tell I think it's a sign of the head dying (not exactly good news).
The player needs to synchronise frames, and I think that if the sync is lost it just shows a blue screen instead of a shakey picture. Maybe the sync signal is just below the threshold that the system is calibrated for (because if the head is getting tired the signal is weaker).
I think that the fast forwarding works because either it uses a different part of the head to read during fast forward motion, or the increased speed of the tape movement increases the magnetic flux just enough to pass the threshold.
Cleaning the head might help ?
This is only an educated guess, so if you ever do find out the real reason, I'd love to know too !!


Return to posts index

Shawn Romano
Re: "Invisible" HDV Footage: Can Only See Footage on Fast Forward
on Oct 24, 2009 at 10:21:39 pm

Thanks Tony, this is a good thought. I will look into it. I hope it's not the case though, because my camera is relatively new and hasn't gotten a ton of use since I purchased it a little less than a year ago!



Return to posts index


maurice jansen
Re: "Invisible" HDV Footage: Can Only See Footage on Fast Forward
on Oct 24, 2009 at 10:28:08 pm

hi there

there are more people having this problem.
if you search the cow you will find people with the same problem.

what i say to every body. don't just don't put in those cleaningtape's
they will kill your head's.

let a experience engineer clean your heads when needed.

greet
Maurice


Return to posts index

David Williamson
Re: "Invisible" HDV Footage: Can Only See Footage on Fast Forward
on Mar 12, 2015 at 10:38:21 am
Last Edited By David Williamson on Mar 27, 2015 at 6:11:26 pm

I just put a brand new tapehead drum, with the tracking adjusted spot-on, in an HV30 and found that the recording signal to the heads is lower than normal. When this new mechanism is connected to a test rig it records and playsback HDV faultlessly. This particular HV30 must have an amplifier problem. The effect is that it can record and playback HDV or DV fine if the tape used is new and blank or has only ever been recorded on and overwritten in this particular camera, which has the weak signal. If you try to record on a tape which has already been recorded on in another camera, with a higher strength recording signal, then this camera cannot fully overwrite the existing stronger timecode signal and on playback there is a loss of locking on to the trigger signal and the image defaults to blue screen. On fast forward HDV does not attempt to lock on to the trigger signal so you can see the poor quality, speeded-up, image (although with a tape which has already been recorded on in a camera with the stronger signal, then over recorded with the HV30 and is then playedback on this HV30, the timecode/date will often flicker rather than count smoothly). Could it be that you are experiencing the same and the tapes which playedback o.k. were previously only used in your problem camera but the one which won't playback had been previously recorded on in a different camera?


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]