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-   -   GL-2 playback problem (https://www.dvinfo.net/forum/canon-gl-series-dv-camcorders/8205-gl-2-playback-problem.html)

Tom Markos March 31st, 2003 09:26 AM

GL-2 playback problem
 
During playback through the GL-2 I have noticed a video image problem. In a condensed form, this is what is ocurring. In the onboard LCD or viewfinder the image appears to be perfect, but when I play back a tape and view it on my monitor I am getting brief, random, horizontal blips across the TV screen. These "blips" ocurr with S video connections or with the RCA, with AC power or battery. I have tried different tapes and different monitors but the problem remains-the viewfinder image is fine, the monitor image is not.
Even in "pause" mode , while viewing a still image, I have these dropouts. Any ideas?
Tom

Rob Wilson March 31st, 2003 09:39 AM

I've seen the same thing and cleaned the head. Problem has not recurred but can't say for sure it was the head cleaning.

Bud Kuenzli March 31st, 2003 12:15 PM

viewfinder lies
 
obviously the viewfinder has to throw out a lot of information. don't rely on that. if you are getting artifacts like you mentioned the first thing is to clean the heads using a cleaning tape. follow the directions and don't overdue it. the gl2 manual says you may have to clean heads up to five times, but instructs you to remove the tape between cleanings and wait a few seconds between cleanings. If a single, or multiple cleanings doesn't do it, you may have to have it cleaned by canon. I'm assuming this is occuring with new, good tapes and you are not swapping tape types (ie using sony at one point and then panasonic later).

Tom Markos March 31st, 2003 12:34 PM

Artifacts
 
Hi Bud, Rob,

Thanks for the response. I have cleaned the heads (one pass just before you replied) and the problem is still there. Even when the GL is displaying a still frame I have the blips. The tape doesn't need to be in motion. Could the problem be in the analog output circuitry? If so, I am seriously bummed because I need this camcorder a lot at the moment and really don't want it to be idled too long.
Remember, these problems are not in the recorded image, only in the playback using the GL-2.


Tom

Jeff Donald March 31st, 2003 01:42 PM

Quote:

Remember, these problems are not in the recorded image, only in the playback using the GL-2.
Huh, aren't you playing back the recorded image? Have you tried the tape on another playback device, VCR or camera?

Tom Markos March 31st, 2003 02:03 PM

Jeff,


I dubbed copies of a few tapes. The dubs are clean and free of any flaws as is the image in the LCD and viewfinder. That is to say, the problem is only evident when viewing the tape on an external monitor. ( I have tried more than one monitor)

Tom

Jeff Donald March 31st, 2003 05:27 PM

Did you dub the copies straight (machine to machine) or through a TBC? Did you see the blips when you were making the copies? If so, where, on the LCD or on an external monitor?

Tom Markos March 31st, 2003 06:52 PM

Jeff,

I fed the GL-2 directly into an SVHS VCR. On the TV monitor I saw the "artifacts", but they do not appear in the copy nor did/do they appear on the GL LCD screen. I guess what I am trying to say is that when the GL is used as a player fed into a monitor I see the problem i.e., it is output related.
Tom

Jeff Donald March 31st, 2003 07:19 PM

Very strange problem. My best guess is the VCR is applying some kind of DOC (Drop Out Compensator). This would mask the artifact on the VHS copies. What you see on a monitor is what is going to tape. If you see artifacts on the screen they should be recorded to tape. If the problem persists I would send the unit to Canon for service.

Tom Markos March 31st, 2003 07:34 PM

Jeff,

Yeah, really pretty strange. Doesn't even appear to make sense, does it? Thanks for the help, it was appreciated.
Tom

Tom Markos April 8th, 2003 09:17 AM

Hi Jeff,

Upon closer examination of the image, I find what you say to be correct; the video recorded to VHS also has the dropouts.

So, to the best of my knowledge, here is what is happening: The GL produces a clean video (I checked it on another deck), the viewfinder and LCD image are also pure. However, what is exported from the GL through RCA or S-Video connections to either an external monitor or recording deck, is not without flaws.

To further compound the problem, and any potential solution, the "artifacts" suddenly have disappeared after two weeks with them constantly evident.

Sporatic problems such as these, I find, are generally the most difficult to resolve and also the most perplexing. Any other ideas?

Tom

Jeff Donald April 8th, 2003 02:12 PM

If it isn't exhibiting any of the symptoms or actual problems, there is no point sending it in for service. The technicians can only trouble shoot what they can see. Since the problems seem to be isolated to the analog output you may want to use another camera to record to VHS until the problem becomes more apparent. Then send it in for service.

Tom Markos April 8th, 2003 06:47 PM

Jeff,

Funny thing happened on the way to the forum...the problem resurfaced immediately after I posted the past message to you. This prompted a call to Canon followed by a shipment of the GL.

I hope to hear from them in about a week.

Tom

Tom Markos April 16th, 2003 08:11 PM

More of the same
 
Well the GL was sent to Canon Service in New Jersey last week and returned to me one week later (Tuesday). This morning I put in a tape and connected the camcorder to a monitor and, of course, the problem is still there...glaringly so.
The technician indicated that he was not able to duplicate the problem but replaced the slide chassis, drive and idler gears anyway. Since I suspected this would be the result, I once again contacted Canon and explained the difficulty .
While there were no answers or even any concrete suggestions as to a solution, a decision was made to send both an original and a duplicate video exported from the camcorder with (anomolies present) to Canon for further examination.
This potential repair is becoming all the problem I suspected it would be. What troubles me even more is that the techs always want to point to a mechanical difficulty and not an electronic one which would seem to be more logical.
Tom

Tom Markos April 22nd, 2003 06:43 AM

Now that both original and duplicated videos are available to the techs at Canon there is agreement that something strange is occurring.
Last night I again mailed out the camcorder and it should arrive within the hour at the service facility. This time the technician is already prepared for the specific problem.
I might know as early as today what the source of the dropouts might be and I'll post the results so that anyone with a similar complaint might benefit.


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