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Old September 25th, 2004, 12:40 AM   #1
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What to expect from a dropout.

My first experience from an audio dropout was from the last event I did.. I finally got through all the footage, and it appears that on two of the 5 tapes I used I had some type of problem. I don't really understand the concept or cause of audio dropouts, but on one tape, I had a 10 frame section with no audio, on the other it was 5 frames. Both happened at key moments, and both were reasonably salvageable, one with minidisc, the other with a 2nd camera just feet away from the main roll, but both caused a noticeable change in the tone of the recording after the repair.

Should dropouts be this long? I thought 1 frame, maybe 2 but 10? Is it normal, or something that I should be concerned with? All I use are Fuji tapes, and no head cleaning messages.
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Old September 25th, 2004, 10:46 AM   #2
 
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Could be a bad place on the tape, could be dust got in there, could be a cable went weird, could be any number of things. Could also be that the converter lost it's own sync and couldn't find sample sync, and that could account for the longer dropout.
Could be that the camera was jostled enough as well. Dropouts to an extent, remain a mystery sometimes...I've had a few that I couldn't figure out for the life of me.
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Old September 26th, 2004, 09:19 AM   #3
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Re: What to expect from a dropout.

<<<-- Originally posted by Chris Thomas : My first experience from an audio dropout was from the last event I did.. >>>>

Errrmmm, . . . welcome to the club? ;)

<<<I had a 10 frame section with no audio, on the other it was 5 frames. Both happened at key moments,>>>

You didn't know that this is clearly stated in section 1a of Murphy's Law?
". . . audio dropouts will occur at key moments, where they shall create
as much trouble as possible . . ." ;)

<<<Should dropouts be this long?>>>

The dropouts that I've encountered are usually 1-3 frames long, but if the tape
is bad, the camcorder gets dirty or has a mechanical issue dropouts can
be continuous.

<<< I thought 1 frame, maybe 2 but 10? Is it normal, or something that I should be concerned with? All I use are Fuji tapes, and no head cleaning messages. -->>>

Sounds like bad tape stock to me. I use only Sony PR or EX miniDV on my own
gear and we use the pro Panasonic miniDVs at The U. It seems like Panasonic
pro stock is really solid. Sony's pretty good except for DVCAM 2 and 3 hour tapes
which I find to be more plagued with dropouts than miniDV . . . go figure.

I think Fuji is made by Panasonic.
Students come in all the time with tape problems. TDK, Maxell and *cheap*
Panasonic and Fuji tapes are not worth the money you save imo.
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Old September 26th, 2004, 10:03 AM   #4
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Strange though, I would think that a dropout big enough to affect audio for so long would also affect video. Are not video and audio signals in DV interlaced and written to tape as a single data stream?

Are you playing back the tape on the camera itself or on another device? It might be some kind of sync problem.

I have never experienced audio-only droputs except this strange problem I get when running the PDX10 in DVCAM mode: when the tape is about to run out the audio breaks up (mutes once or twice) and then dies a few seconds before video does. Very weird, and never happens in SP mode.
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Old September 26th, 2004, 10:44 AM   #5
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Many times with audio drop outs a video problem occurs too,
but not always. Audio seems like the first thing to blip.
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Old September 26th, 2004, 03:00 PM   #6
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Quote:
Strange though, I would think that a dropout big enough to affect audio for so long would also affect video. Are not video and audio signals in DV interlaced and written to tape as a single data stream?
That is what I thought... Especially for a 10 frame dropout, but the video is perfect, no artifacts, nothing. I would of thought that if it was bad tape, the video would likely have been affected too.
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Old September 26th, 2004, 03:12 PM   #7
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Tried playing it back somewhere else?
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Old September 26th, 2004, 03:14 PM   #8
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I have tried playing it on 2 cameras. Both with the same results.
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