Call On All Hv20 Owners - To Test For Dropouts

[Chris Barcellos]

Okay Guys, I had to chime in here.... I am using $3.00 TDK tapes from Costco, and I am just no seeing any drop out issues. I do sometimes wonder how accurate the camera is with respect to appending new footage after the camera is restarted, because I notice blank spots and time code restarting in some situations, but I just haven't seen any drop outs during a shot, at this point. This includes the 3 hours of shooting I did for 48 Hour Film Project film last month.

[Peter J Alessandria]

Already chimed in here: http://www.hv20.com/showthread.php?t=1288 and here: http://www.hv20.com/showthread.php?t=1181

[John Hotze]

Originally Posted by Peter J Alessandria

Already chimed in here: http://www.hv20.com/showthread.php?t=1288 and here: http://www.hv20.com/showthread.php?t=1181

OK Peter. I hear what your saying, that you think it's 99 percent, or some high percentage, of the dropouts are do to dirty heads. I have to disagree with you. I just don't think all of us, or even 50 percent of us experiencing dropouts, due to dirty heads. How can we test this and come up with a scientific conclusion as to where the dropouts are or aren't coming from? It may be difficult and time consuming but maybe it would be worth the effort.

I think that Tony is probably dead on with his I-Frame summation. If a bit doesn't get written correctly in an I-Frame it screws up a bunch of frames. Before I-Frame (which I'm guessing came along when HDV did) a changed bit in one frame didn't do that much like a bad I-Frame bit would. Doesn't this make sense as to why we're discussing much more dropouts than were happening with our SD cameras? I'll be honest, I've been shooting videos for 3 years (about 300 archived on my sheves right now) and never owned a tape head cleaner until a month ago and I've only taken it out of my bag once. I think even than, it may have been because of you Peter & that's because I respect your opinions here a lot.

To me it only stands to reason that if the head cleaner has even a mild abrasive in it, you wouldn't want to use it very often. Can we find some unbiased documented information about the use of mini dv tape head cleaners somewhere. I'll go do a little Googling around and if I come up with something, I'll post it here.

[Pedanes Bol]

I use TDK tapes from Costco. I am currently on the third tape and I noticed two drop-outs overall so far.

[Peter J Alessandria]

Originally Posted by John Hotze

I think that Tony is probably dead on with his I-Frame summation. If a bit doesn't get written correctly in an I-Frame it screws up a bunch of frames. Before I-Frame (which I'm guessing came along when HDV did) a changed bit in one frame didn't do that much like a bad I-Frame bit would. Doesn't this make sense as to why we're discussing much more dropouts than were happening with our SD cameras? I'll be honest, I've been shooting videos for 3 years (about 300 archived on my sheves right now) and never owned a tape head cleaner until a month ago and I've only taken it out of my bag once. I think even than, it may have been because of you Peter & that's because I respect your opinions here a lot.

To me it only stands to reason that if the head cleaner has even a mild abrasive in it, you wouldn't want to use it very often. Can we find some unbiased documented information about the use of mini dv tape head cleaners somewhere. I'll go do a little Googling around and if I come up with something, I'll post it here.

If I understand you, I think we're saying the same thing. Dropouts are more noticeable on HDV because of the long GOP encoding - that means 15 frames gone per dropout compared to one frame (intraframe compression) for DV. It's essentially a 1/2 second freeze of the image. Talk about in your face. But I-Frames don't cause dropouts - dirty heads do.

Dry-type head cleaning tapes are abrasive so you don't want to use one more than necessary. And only for 10 seconds at a time. But I think the camera will fail for other reasons long before head wear due to occassionally using a cleaning tape.

I may be wrong, but it seems to me Canon has pretty low quality control on things like dirty heads on the HV20 and dusty sensors on their DSLR's. I've used three brand new DSLR's from Canon and all had filthy sensors. Given how many people have reported dropouts/freezes on new HV20's (including me), those heads must be clogged from the factory. I've run my cleaning tape 2 times (~20 secs.) so far and the amount of dropouts dropped pretty significantly.

So... is the camera defective? Personally I don't think so. But I guess we'll see...

[Bob Harotunian]

Just a quick thought. From my experience, the first and last 30 seconds of a tape are more likely to produce drop-outs. Also, as most of you already know, switching between Sony and most other brands of tape may result in head clogs and drop-outs. Pick a quality tape brand and stick with it.

The HV20 or any camera should be able to run for an hour without issues. We produce weddings and ceremonies are often 45 to 60 minutes long. If you're camera handling is rough or you bump it often, expect problems. This is an inherent problem with small, lightweight cameras like the HV20.

For those of you experiencing multiple drop-outs, why haven't you sent it back to Canon?

[John Hotze]

Originally Posted by Bob Harotunian

. For those of you experiencing multiple drop-outs, why haven't you sent it back to Canon?

Because shooting HD, it's normal to have occasional dropouts. If that wasn't a reality, practically everybody who owns one of these new HD camcorders would be shipping them back. Tapes are not always perfect & as Peter has pointed out, heads get dirty occasionally, & lastly, I can live with a few occasional dropouts.

[Bob Harotunian]

Something's not adding up here. There are many people who have gone HD on other forums and my local NPVA and I have not heard about HDV drop-out issues. For all event videographers, any drop-out equal to 15 frames could be disastrous. If it were true that drop-outs are systemic with HDV, why would anyone go HD for wedding coverage as an example? One drop out per hour is one too many.

Years ago, I used an Elura for capture and experienced occassional A/V drop-outs. But, when I recaptured, they were often gone indicating it was a problem with the capture device. For those of you with multiple drop-outs per hour, are you capturing with your HV20 and are you sure the drop-outs are on tape?

For years I have followed this forum and read many problems reported by GL2 users. Yet, we produced weddings with GL2s with no problems for 3 years. That makes me think that sometimes reported issues on forums may not be issues at all.

That being said, I'll be monitoring other forums for HD drop out problems. If there truly is a problem with the HV20 or especially the more popular prosumer models, then I'm staying SD.
Bob

[John Hotze]

Originally Posted by Bob Harotunian

Something's not adding up here. There are many people who have gone HD on other forums and my local NPVA and I have not heard about HDV drop-out issues. For all event videographers, any drop-out equal to 15 frames could be disastrous. If it were true that drop-outs are systemic with HDV, why would anyone go HD for wedding coverage as an example? One drop out per hour is one too many.

Years ago, I used an Elura for capture and experienced occassional A/V drop-outs. But, when I recaptured, they were often gone indicating it was a problem with the capture device. For those of you with multiple drop-outs per hour, are you capturing with your HV20 and are you sure the drop-outs are on tape?

For years I have followed this forum and read many problems reported by GL2 users. Yet, we produced weddings with GL2s with no problems for 3 years. That makes me think that sometimes reported issues on forums may not be issues at all.

That being said, I'll be monitoring other forums for HD drop out problems. If there truly is a problem with the HV20 or especially the more popular prosumer models, then I'm staying SD.
Bob

Bob. I can tell you in my case and I assume this is relevent to what you're saying about capture. I frequently sit back on my couch and watch the tape I'm capturing to my computer by connecting the HDMI cable to my HiDef screen as Pinnacle does it's thing on the computer. With pretty much frequency I will frequently see maybe one dropout per tape as I'm watching it on the big screen. Now what I should do is note the place or time on the video and go back to it after the capture has completed and just play it to the big screen and see if it drops out at the same place. That would be good too know. I had wondered the same thing that you mentioned but with so many of us reporting drop outs and we surely are not all using the same capture program, it leads me to believe it's not a capture problem. Read some of the comments on a similiar thread over on the HV20.

Yeah! I guess it might be bad if the video dropped out just about when he said "I da da da da do". Maybe you better practice the use of "voice overs" - over dubbing. Think they might notice? No - All kidding aside, if I was shooting weddings, I would be investing in the best quality tape I could purchases, which at the very least, would mean scaling up to HD minidv tapes.

[Peter J Alessandria]

I've only captured about three hours of video so far from my HV20 to my computer and haven't noticed any dropouts (I've shot maybe 15 hours total so far.) Today I was watching footage playback from the camera on my TV and on the second viewing there were two dropouts where on the first go round there were none. Can anyone confirm that the dropouts they're seeing are really recording dropouts, and that we're not just seeing playback problems with the camera?

In a way it doesn't really matter if the dropout is generated while recording or only on playback, since the only good dropout is none. But at least if it was just a playback problem and the data on the tapes was otherwise intact, there'd be less worry around this for mission critical recordings like weddings.

[Bob Harotunian]

Peter,
Can you play that tape on your HV20's LCD to confirm the drop out occurs at the same location? Better yet, can you play it on another device or try capturing it as SD on a more robust editing deck like a DSR-11? In my mind, if the drop out moves around or is intermittent then it's a playback and not recording issue.
Bob

[John Hotze]

Peter

I'm going to make it a point to stop, rewind, and play back the place where I see a dropout the next time I'm watching a tape on the big screen. Like you say, no matter why or when it's happening, it's bad. At least if it was a glitch that didn't repeat itself, we have a chance of capturing a clean clip by recapturing. It's kind of like when I go to troublehoot someones computer, I always ask, "Is the problem repeatable". Most likely if they say no, than I tell them it was most likely a glitch and there isn't a whole lot I can do until it starts happening more often.

[Ian G. Thompson]

Originally Posted by Peter J Alessandria

I've only captured about three hours of video so far from my HV20 to my computer and haven't noticed any dropouts (I've shot maybe 15 hours total so far.) Today I was watching footage playback from the camera on my TV and on the second viewing there were two dropouts where on the first go round there were none. Can anyone confirm that the dropouts they're seeing are really recording dropouts, and that we're not just seeing playback problems with the camera?

In a way it doesn't really matter if the dropout is generated while recording or only on playback, since the only good dropout is none. But at least if it was just a playback problem and the data on the tapes was otherwise intact, there'd be less worry around this for mission critical recordings like weddings.

Hmmm...logic tells me that's the behavior of dirt on the tape heads. If it was not there once but showed up the second go round then there is something moving over the tape heads causing this interferance. Maybe for some unknown reason these tape heads are more prone to collecting dust. Being that it just reads 1's and 0's coupled with the long GOP architecture any little interferance would cause this dropout.

[Clayton Moore]

So I never have any issue in capturing and making DVDs or QuickTime movies. IT all works great.

There does appear however to be odd behavior when playing back from the camera to (as an example) any of my HDTVs. Its intermittent and does not appear to be specific to any place on a given tape.

I will get a freeze for a few seconds then it will continue playing. The tape never stops but its like the data stream gets interrupted or something. It looks like a freeze frame then it starts to pay again.

The same tape will capture to the HD and make perfect unaffected DVDs or QuickTime movies. It may be HDMI related Im not sure yet.

Anyone else seeing this one?

[James E Lee]

Greetings:

Has this dropped frames problem been resolved by Canon? I bought an HV20 from B&H back in December and although I've only recorded one full tape, I didn't get any dropped frames when I transferred it to my laptop. I plan to test this somemore on my new HV20.