XH-A1 picture freeze

Arthur.S wrote on 7/11/2012, 7:18 AM
One of my Canon XH-A1 cams is showing an odd 'freeze' sporadically. It's always around the 10 to 12 minute mark, but not on every tape! The picture freezes to a still for 1 or 2 secs together with total audio drop out. Tried a head cleaning tape, but no difference. (I normally use a head cleaner about once every 6 months or so) I'll add that this isn't just on capture - it's on playback with the cam too. Very minor at the mo, (Maybe once in 4 tapes) but you just know that sooner or later it'll happen at a vital point. Any ideas folks?

Comments

videoITguy wrote on 7/11/2012, 7:51 AM
Are you recycling over previously used tape in your camera. In other words did you shoot 108060i and then rewind and shoot right over the same tape region with settings 108060i?

Just an FYI - you should not do it this way...write back if this is what your shooting method has been.
Arthur.S wrote on 7/11/2012, 1:23 PM
Not 60i (I'm in PAL land) but yes, I'm reusing tapes. I've always done this, as I see them as a 'known good' item. Never had this problem before. But....maybe as the cams get a bit older the tolerances get tighter?
JJKizak wrote on 7/11/2012, 1:57 PM
I had an audio dropout problem (new tapes only) with the old Canon 4 x 3 and they told me to keep running the cleaner tape through it. The sound quality was excellent however and the AGC was one of the best I have used. The cleaner tape would work for a while but didn't seem to eliminate the problem.
JJK
videoITguy wrote on 7/12/2012, 12:56 AM
Arthur.S
I have no idea how familiar you are with tape tech, but I would imagine that you really don't want to go there anyway.

The fault you are describing is most likely a symptom of the helical scan and tracking failing because,
1) Tape surface defect/ or dirt introduced into the scan read/write
or 2) the fact that you are recording similar and overlapping tracking paths of similar standards (ie. you pal setting) over the same section of tape.

YOU should never pass or recycle your tapes for critical camera shoot for more than 3 cycles. Period.
Here's why, The chance introduction of dirt into the drum and head assembly increases with every loading and unloading into the tape compartment. Consider factory packaged tape virgin, after that you definitely have contaminants affecting every recording pass.Now most people will just tell you to clean the compartment - but it really does nothing for a contaminated tape - just toss it.

FOR the SECOND cited reason cited above, you do have a chance to recycle tape (upto 3 times) - and if you have a camera that will do this to ingested tape. First pass shoot in your preferred mode, second pass -stripe the tape with color bars -great idea- in a radically different recording mode - say change 50i to 30P- then third pass prepare to shoot in your regular settings mode once more. As you can see this technique yields only 2 useful recordings. The reason for doing this - keep radically different tracking patterns erasing and overlaying the previous track so that the next pass records as best as possible a new virgin path and successful track.
Arthur.S wrote on 7/12/2012, 7:28 AM
Thanks for that info. I've always re-used tapes up to 5 times then tossed, (Interesting to see if the forum censor removes that word or not :-) ) but never bothered with 'striping' as I see it as an unnecessary wear of the recording heads. (I've had these cameras for around 4 years) Would striping with say an old SD camera for the 2nd recording work the same?

I've got a shoot coming up in about a week, so will use ALL new tapes to see if that's the problem. Are there any other cleaning solutions I can do myself other than a cleaning cassette? If not, are any cleaning cassettes better than others?
videoITguy wrote on 7/12/2012, 9:45 AM
I take your question to mean can you move a tape from an HDV camera and recycle it in a native SD camera /?- yes, maybe, but this process introduces more shuttles between compartments and you are likely to make the more sensitive HDV camera tracking even more problematic by contamination from the SD machine if you choose to bring it back to HDV. I wouldn't.

Cleaning tapes are a total misnomer, they do nothing more, and maybe are worse than just placing a hi-quality virgin name brand tape in the machine as your "cleaning" cycle tape.
Arthur.S wrote on 7/12/2012, 12:55 PM
So would a 'professional' clean be worth while?
videoITguy wrote on 7/12/2012, 1:39 PM
IMO the only "professional" tech touching my equipement is a trained camera repair person..if you need to go that far.

For yourself to diagnose whether the camera has tracking problems do this 1) record on virgin tape your standard choice format of a single color -choose grey card for example with camera solidly mounted on tripod. For sound, feed audio port simultaneously with a good quality music source with a fairly intricate melody. Record a 10 minute session 2 minutes ahead into the tape. (Never use the head of the tape for recording..you know this).

Now that you have a recording on tape watch and study this tape section intently to see if you notice any anomalies. They will show up quickly if your camera is misbehaving. Now hook up to your NLE with firewire and capture brief random 30 second sessions of the 10 minute section with camera control onboard your NLE/&PC OS system. Rock and roll the tape rapidly between ffwd and rewind sessions of capture. If your camera is misbehaving - you will hear evidence of the sound possibly garbled at the begining of new subesequent takes. If the camera can do all this and pass - then of itself - it should be good.
Arthur.S wrote on 7/13/2012, 1:12 PM
Many thanks for your input videoITguy. I'll take note.