View Full Version : Dropouts on the first 6-8 minites of tape
Frank Spangler April 2nd, 2009, 11:24 AM I have just ordered my third XH A1 which I hope shows how much I like this camera... But I have had the same problem with my first two. After about a year of use, I get severe dropout issues on the first 6 to 8 minites of tape, with virtually no problems after that point on the tape. I am wondering if others have experienced this problem ... Is it something that can be serviced cheaply or is it a head replacement thing...
I use Panasonic AY-DVM 63AMQ tape
Frank
Bill Pryor April 2nd, 2009, 12:23 PM Sounds like dirty heads. Have you used your head cleaning tape?
Allan Black April 2nd, 2009, 07:49 PM As Bill said; and the collective consenus is to run your cleaner tape first before shooting anything, to clean the heads.
It's mighty possible Canon tested your cam with a wet lube tape and you're running a dry type there.
Cheers.
Richard Gooderick April 3rd, 2009, 02:40 AM If you use a tape cleaner every time you use the camera isn't that going to wear the heads prematurely?
Tripp Woelfel April 3rd, 2009, 06:33 AM I'm with Bill on this. If I had this issue, the first thing I'd do is clean the heads. I have had my A1 for over 18 months and not experienced your symptoms and I use the same tapes that you do.
It's interesting that you've had the same problem on two cameras. You don't state whether you purchased them at the same time but if you did it's possible that you got a dodgy batch of tapes. Having the same problem crop up on two cameras at the same time would indicate to me that it might not the cameras, but the tapes.
If you search these lists, you'll find information on some bad Panny tapes. I'm a little fuzzy on recollecting the details, but I don't think the issue was exactly the same as yours. However it might be related. Combine that with the fact that I have not read any reports about the A1 experiencing your problem and I think that the root cause does not come from your camera. I could be very wrong but the trail of logical bread crumbs does not point me in that direction.
Allan Black April 3rd, 2009, 07:36 AM If you use a tape cleaner every time you use the camera isn't that going to wear the heads prematurely?
Being honest I don't know. The HV20 manual says 'clean frequently' but doesn't say the hourly rate, so I'd guess it's every 5hours of rec/play tape use.
But after 46years experience with magnetic recording tape here's what I believe.
This is based on prosumer DV tape use.
Panasonic (for instance) says, change the head after 1000hrs use, that's one heck of a lot of tapes, work it out. If used for 3hrs a week average (and that's a lot) and 2x60min tapes, that's nearly 6.5years and about 670 tapes.
No one I know has ever had to do that, they updated their prosumer camera well before the 1000hrs. And at 1000hrs the heads don't just drop dead, it means they are well worn, you've got your money out of them, so change them for new ones before trouble starts. They also renew the tape guides as slots or grooves wear in them as the tape runs.
So I fail to see how running a DV cleaner tape for 10secs 'frequently' will damage the head, frequently being about every 5 to 10hrs use, more often if you get airborne microgrit then tape dropouts in the transport.
I think the 'damage the heads' thing has blown up out of proportion over the years but by the same token don't run the cleaner every time you change tapes and/or for no longer than 10secs at one time. Follow the instructions and I only use cleaner tapes once. IMHO.
Cheers.
Bill Pryor April 3rd, 2009, 09:46 AM You wouldn't want to run the head cleaning tape before every use. Once when the camera is new, and about every 30-50 hours is what most people do, I think. I also use mine after shooting in dusty conditions. Back in my Betacam days a Sony tech recommended every 50 hours, and I did that and always got maximum head life. Fortunately heads last longer on today's small cameras than they did on much more expensive Betacam cameras out of the past. Of course, if you reuse tapes or use bad tape stock you'd want to clean the heads more often.
Also, it helps to follow the old standard procedure of recording 30-60 seconds of bars/tone at the head of every tape, then checking the last few seconds of that to make sure there are no dropouts. If you can't do it for every tape, at least do it for the first one of the day.
Frank Spangler April 3rd, 2009, 01:17 PM It's interesting that you've had the same problem on two cameras. You don't state whether you purchased them at the same time but if you did it's possible that you got a dodgy batch of tapes. Having the same problem crop up on two cameras at the same time would indicate to me that it might not the cameras, but the tapes.
I suspected a bad batch of tapes the first time around, but to have the same problem with the second camera (Purchased after the first one went down) is making me ask the question about head wear. I am afraid that I do put a lot of stress on my cameras. I am not a wedding photographer .... I am out in the ellements, wind, rain and dust. Of course I use the cleaning tape whenever I run into dropouts, I rarely review tape in the field, try and use care where I change tapes, etc
What I don't get is that the problem is consistant with the first 6-8 minites of tape and then NO dropouts for the rest of the tape. I don't understand how that could be...
I would estimate that both cameras had about 400 hours of use on the head when the problem showed up.
Are you saying that I could probably send in the cameras for a good factory cleaning and they would be OK for another 600 hours?
Allan Black April 3rd, 2009, 08:28 PM What I don't get is that the problem is consistant with the first 6-8 minites of tape and then NO dropouts for the rest of the tape. I don't understand how that could be...
I would estimate that both cameras had about 400 hours of use on the head when the problem showed up.
I'd bet it's not faulty tape. Tape dropouts are caused by airborne microgrit getting in the transport.
I think microgrit got in your transport, it got shook up in moving the A1 and into the tape path and on the head. The first 6-8 minutes of stop/start tape 'cleaned' it off causing those dropouts.
Are you saying that I could probably send in the cameras for a good factory cleaning and they would be OK for another 600 hours?
Only if you then follow this suggested cleaning procedure (and don't cause any other damage) heads and tape guides will wear out quicker if you don't. After 400hrs use, a service should realign other things too, ask your centre.
Always wipe the cam body clean before changing tapes especially around the tape carriage area. Have the new tape out ready to put in and have the tpt open for the minumum time, in a dust free area.
Put the full tape away, don't leave tapes lying around out of their cases.
Indoors I upend the open cam giving it a light shake using a blower brush to remove the loose dust then occasionally run a small Dustbug vacuum cleaner before putting in a new tape. If you're going into a dusty area to shoot with a half full tape loaded, put a new one in before you go out. If you have to change tapes outdoors, do it under a clean towel.
Cheers.
Michael Padilla April 6th, 2009, 03:08 AM I too am having problems with tape dropouts.. I can count on about 4 dropouts per tape using the xha1 and Panasonic pq tape. I have had my two cameras from new, and they have always exhibited some sort of drop out issue. I do clean my heads (not frequently/aggressively) but it doesn't really make a noticeable difference.
I am thinking about switching to Sony tapestock, but I get a fresh supply of PQ or AMQ at a very low price.. if not free at times (because of shared resources).
Any additional help would be appreciated.
..on a side note, I just picked up a used xlh1 (that is like new) and am running the same tape stock.. with zero dropouts. Did canon use different heads on the XL vs the XH cams?
Allan Black April 6th, 2009, 03:56 PM ...on a side note, I just picked up a used xlh1 (that is like new) and am running the same tape stock.. with zero dropouts. Did canon use different heads on the XL vs the XH cams?
So that discounts the tape as your dropout cause. I can't imagine Canon puts a different head in the XL to the XH.
IMO if you shoot in a dusty location just once, can cause drop outs in following tapes. I'm not talking about clouds of dust swirling about, just maybe outdoors in the city or near a freeway or a windy day. All it takes is a few minute specks in the your tape transport.
Early last year I had none for about 6 new A1 Pana MQ tapes and after a dusty shoot, 4 dropouts in the following tape, then more later. Ended up giving the A1 the full cleaning routine.
I shoot on airfields and nowadays cover all exposed ports with low tack Cling brand tape and cover the A1 with a large plastic bag during downtime. A good way to see the dust is, later use a mag glass and check the front of your lens filter. I see a light coating overall, always use a blower brush first.
TBO I don't think folk take enough precautions against DV tape dropouts.
Cheers.
Mike Hardy April 6th, 2009, 07:01 PM My XH-A1 is only around 3 hours old, perhaps a bit less. I also use this brand of tape, panasonic ay-dvm63amq, and on every shoot I have experienced flaws or faults. I do not categorically state they are dropouts because I am uncertain as to what a dropout is, but I am definitely experiencing some fault. Heavy artifacts, combined with freeze/juddering for a brief second or so. Curiously enough, it tends to be between a quarter and half way through a tape, and only briefly.
Michael Padilla April 6th, 2009, 08:28 PM Also I have noticed that sometimes I will get more or less drop-outs on import when trying a re-import.. for example I imported a tape today; got a dropout within the first few seconds of shooting.. so since I caught it and it was so early in the tape.. I stopped import and started over..
second time around there was no drop-out on that frame. Reasons?
Alan Craig April 7th, 2009, 12:19 AM Panasonic (for instance) says, change the head after 1000hrs use, that's one heck of a lot of tapes, work it out. If used for 3hrs a week average (and that's a lot) and 2x60min tapes, that's nearly 6.5years and about 670 tapes.
Cheers.
Allan JVC quote 2000hrs I had one occasion when I had over 600 dropouts on one tape using my XHA1 I used a head cleaner and that sorted it, there was nothing wrong with the tape because it worked perfectly after using the cleaner.
Alan
Alan Craig April 7th, 2009, 12:24 AM My XH-A1 is only around 3 hours old, perhaps a bit less. I also use this brand of tape, panasonic ay-dvm63amq, and on every shoot I have experienced flaws or faults. I do not categorically state they are dropouts because I am uncertain as to what a dropout is, but I am definitely experiencing some fault. Heavy artifacts, combined with freeze/juddering for a brief second or so. Curiously enough, it tends to be between a quarter and half way through a tape, and only briefly.
Mike I don't know what nle you are using but I use Pinnacle 11 and that shows me how many drop outs there are as I am tansfering footage.
Alan
Frank Spangler April 7th, 2009, 06:55 AM I think microgrit got in your transport, it got shook up in moving the A1 and into the tape path and on the head. The first 6-8 minutes of stop/start tape 'cleaned' it off causing those dropouts.
Cheers.
I understand about dust and it would be my first suspect as well, given the environments that I shoot in, but what I don’t get is how dust could cause this kind of problem on the first 8 minutes of tape and then cause no further problems for the rest of the tape. Please understand .... this is not just one tape. This has been a consistent problem over the last 30 tapes that I have used in this camera. I am not talking about little glitches, I am talking about dropouts so bad that the tape cannot be captured at all for 30 second chunks and then it may capture 10 clips that only last a couple of seconds each, and then go completely blank for another 30 secs. (I have set my editor to automatically break clips up at a time code break)
Then, after about the 8 minute mark I get NO dropouts at all. This is the exact same thing that happened with my first camera so I am just wondering if it could be a head wear issue and for some reason the first 8 minutes of tape is no longer making good contact with the heads ....
As a work-around I just started putting 8 min of bars on tapes before I started shooting, but it still leaves me nervous enough to not go out on my next shoot with out a new camera. I can't take the risk of shooting interviews in SE Asia only to get home and find out that they are full of dropouts.
I appreciate your advice about keeping the camera out of the dust as much as possible. I also cover all of the cracks with tape, however, I know that I could do better. I have tried the Portabrace covers, but find that it impedes my shooting. What to do ....
Bill Pryor April 7th, 2009, 08:52 AM Have you tried using your head cleaning tape and then switching tapes to something like Sony's Digital Mastering tape? I had serious trouble with those Panasonics; now I use the Sony PHDVM and haven't seen a dropout since I switched. Of course they cost twice as much; even so tape is cheap.
Richard Gooderick April 8th, 2009, 02:38 AM I had one drop out in the middle of an important, non-repeatable performance using the cheaper Sony tapes.
For any shooting that is critical I now use the more expensive ones (that say HD on them).
I haven't had any problems using the more expensive Sony tapes. But I haven't had any further problems with the cheaper ones either!
Greg Clark April 9th, 2009, 07:18 AM Sony or TDK has never failed me. Panasonic had failed me many times until I stopped using them.
Bill Koehler April 9th, 2009, 10:10 AM Also I have noticed that sometimes I will get more or less drop-outs on import when trying a re-import.. for example I imported a tape today; got a dropout within the first few seconds of shooting.. so since I caught it and it was so early in the tape.. I stopped import and started over..
second time around there was no drop-out on that frame. Reasons?
One of the things I do before a shoot where I'm using tape is to fast-forward the tape to the end, then rewind it back to the beginning. The theory of operation is to get uniform tension on the tape, with no points of unexpected slack, so while shooting tape movement is as consistent as possible.
My guess is your tape had a small amount of slack. Running the tape took it out, so when you rewound the tape and played it again everything was AOK.
Kyle Root April 9th, 2009, 10:22 AM I have been using Panasonic miniDV tapes since 1999 and have only had ONE occassion where the tapes used were guilty of major dropouts that were uncorrectable.
It happened at a wedding where we were using 2 Sony VX2000's and both cameras exhibited the exact same 'noise' and massive pixelation issues that last the entire tape on both cameras. Everything was -blocky- and looked like a 1980 atari video game.
In the past 10 years, and after filming hundreds of weddings and other events, there have only been maybe a dozen instances where we have even had llike a 1 sec blip on tape. Aside from the above event which was a disaster, we have never had any issues with panasonic tapes... and we order batches of about 150-200 every year from B&H.
So to have only a handful of 'issues' out of 1500-2000 tapes... not too bad.
The other thing I will say is, early on, we learned that using the EP mode (where you get 90 min out of a 60 min tape or 120 min out of a 80 min tape) caused most of our issues. Since we had 5 different cameras (2 GL1s, 2 VX2Ks, and 1XL1s), tapes recorded on one, were not able to be played back on another without significant dropouts and pixelation.
Once the tape was placed back in the camera it was recorded on, everything was fine.
So lesson learned there is, be careful when using EP mode too!
|
|