Mosaic pattern, tape, electronics, heads?

[Richard Novick]

I own two GL-2s, and I've noticed an annoying problem for some time that's common to both cameras. Intermittently, I detect a "flash" in the footage. Upon further investigation, the "flash" turns out to be a mosaic of pixels confined to as little as one frame. This occurs anywhere from one to five times in a 60-minute tape, and it's fairly random with respect to where on the tape it occurs.

I've found very little information from either Canon or on message boards that addresses this problem. I'm inclined to rule out "dirty heads" because 1) I've cleaned the heads and it still occurs and 2) I'd like to believe that if the heads were dirty that the irregularity would be more frequent and cover a wider area than a single frame and only do so twice on a 60-minute tape. I'm open to other views on this.

Is what I'm seeing considered to be a tape "dropout?" I'm using Sony Premium tapes. They were strongly recommended by service staff at the Canon repair center in Irvine.

An associate of mine suggested that the problem might be electronic in that if we consider the mosaic to represent missing data, then perhaps the GL-2 is not transmitting full data to the tape.

Overall, I'm baffled by this and would welcome any input that anyone might have.

[Ken Tanaka]

My opinion is still dirty heads. Are you re-using tapes heavily? Are you consistently using a brand and grade of tape or do you use a variety of brands. How long have you owned these cameras / have they been used hard? Have they ever received Canon service?

[Richard Novick]

Thanks very much for the reply. To answer the questions you've raised, one of the GL-2's is about six months older than the other. The older one was purchased in December, 2002. The newer camera has never run any other brand of tape than Sony Premiums. The older camera has had a variety of tapes brands run through for playback, but only the Premiums for recording. The older camera is almost exclusively used now in my non-linear editing setup which involves playback of 3 to 4 tapes per month for capture and an equal number of recorded DV masters. To me, it's use is fairly light or moderate at the most. The newer camera is used primarily for recording in the field, about three to four times per month. Again, I think that's light to moderate use. The older camera has been in for service at Canon in October and November, 2003, for rewinding problems. They presumably replaced the entire recording assembly. Neither camera has ever had the heads serviced.

[Ken Tanaka]

Richard,
Clearly, you're very conscious of how you're using your cameras...a good camera daddy! <g> In general, when facing such intermittent glitches we're in guesstown. Some might say that Sony tapes tend not to play nice with Canon cameras. (Canon's own "brand" was, and perhaps still is, Panasonic tape.) But I don't really buy this as fact.

The basic symptom you descibe is classically that of head contamination. If conventional cleaning does not bring remedy, perhaps a Canon service cleaning will be the last resort. XL1s owners are encouraged to send their cameras to Canon annually for cleaning and tune-up.

[Frank Granovski]

Richard, your problem is classical dirty heads. In fact your problem is described in detail in my JVC manual. So I doubt it's the cam that's at fault. Here are some tape links:

http://www.dvfreak.com/tape.htm