XL1: Capture on different camera = audio noise?

[Greg Chabon]

I'm shooting on the XL1 (panasonic tapes) then playing back and capturing on a Samsung SCD23. Video is fine but audio "squeals" on playback. I'm capturing to iMovie HD6 on an Intel iMac via firewire. If I use the "filter audio" option in iMovie it chops up the audio badly (trying to filter out the squeals). If no audio filtering, it squeals during playback, but here's the very odd part: once captured you can run the clip in iMovie and the squeal is gone. The squeal is is not mechanical -- volume control on the Samsung affects the overall audio level including the squeal. Does not appear to be feedback as the Samsung onboard mic is not enabled during playback.

FYI, no problems of any kind (audio or video) playing back on the XL1 (I want to use the older Samsung for capturing to save the XL1 heads).

I'm concerned that the squealing is indicating some larger problem (heads?), and in any event I'm sure it's somehow degrading the audio (I have not yet done extensive A/B testing of clips captured from the XL1 and the Samsung to compare).

Anyone have any thoughts on this issue? Thanks in advance.

[Lorinda Norton]

Hi Greg,

From what I’ve read here over the years it’s usually the video that acts up when shooting on an XL1 and capturing/playing back on another camera, but your problem sounds similar. With mine I finally chalked it up to slightly misaligned heads on my XL1s but chose not to get it fixed—mostly, because I figured my previously shot tapes wouldn’t play correctly anymore. That’s not proven, of course, but seemed like the most sensible conclusion, and I've been happily shooting and capturing ever since using my XL1s.

The idea of saving wear on the heads has been discussed a lot over the years and I always go back to what a guy here told me over five years ago. He said I’d be ready for a new camera before I wore out the heads, and so far, he’s been right. As I said earlier I’ve used mine for capture this whole time and not had the heads replaced. Sure, it’s having problems now, but not from worn heads. It’s just old. If I were in your spot I’d save myself aggravation and go with the simplest solution of capturing and playing back on your XL1.

[Mathieu Ghekiere]

I've encountered the same problems lately: capturing footage of my XL1s with my Panasonic GS200, audio is bad, constantly glitches and stuff.
Don't have this if I capture with the XL1s, and didn't use to have the problems.

Not a nice thing to do, but I don't have the budget to buy another camera...

[Don Palomaki]

Sounds (no pun intended) like a subtle tracking issue that results in tape read errors. This could be the result of the camcorder or playback deck "aging" and the head alignment drifting over time, or possibly head wear that results in a weaker signal reading off the tape. You may not see it in the video because the video has better error correction.

Try play some old tapes recorded before the problem was noticed if you can. If they are OK on the playback deck, it may well be the XL1 that has changed over time. If not, it is likely the playback camcorder.

Also, sometimes PC can have issues during capture causing a stumble, especially if the drives are highly fragmented or getting full.

FWIW: heads should be good for about 1000 to 2000 hours of total ON time. That includes time in record, playback, and pause modes. That can be a lot of tape.

[Greg Chabon]

Well, cleaned the heads of both the XL1 and the Samsung, and same problem. Confirmed that it only makes the noise during capture over the iMac speakers. The noise is not actually picked up on the audio track because once captured I can play the clips and the noise is not there. It's a real high freq. squeally noise. Could the different bit rates of audio be an issue? I record on the XL1 in 20bit but the Samsung's native audio is only 16 bit.

I suppose it's not a huge issue since the captured audio seems fine, it's just that inexplicable noise during capture (and it's not mechanical or feedback near as I can tell as I've zeroed the on-camera volume on the Samsung when capturing).

[Mathieu Ghekiere]

I've had the noise not only during playback, but also afterwards, in my digital files.

[Greg Chabon]

Following up on this issue -- here's another quirk I'd appreciate some thoughts on.

For a home use shoot, we re-used a tape (same brand as the new ones we use) in the XL1 that was originally shot on the cheap-o Samsung SCD23. The resulting footage had "interlaced" images of the old tape scenes and the new ones, in addition to the squealing noise.

It certainly seems (to my untrained brain) that what I'm seeing is head "misalignment" between the two cameras. My questions are (a) is that the case, and (b) if so, does that mean the XL1 needs some maintenance or is that just the nature of using 2 different cameras?

thanks

[Don Palomaki]

First, if using LP tape speed, all bets are off. Interchangeability of tape among different camcorders will be problematic.

The interlacing of old video could be a head alignment issue (but not clear which machine would be off). Testing with a known good third machine can help narrow the problem. But a perhaps more likely a partially clogged or worn head that is not providing a strong enough signal to fully write over the previously recorded material on the tape.

The noise is probably a strange interaction with the software during capture. During that process the machine is very busy. If the captured video is OK, you can live with it since it does not effect the video, or look into machine tweaks to address the issue.

BTW, the standard DV audio bit depths are 12- and 16-bit. Never heard of 20-bit audio in a MiniDV camcorder.