View Full Version : Old footage/New footage interlaced?!


John Locke
November 9th, 2001, 09:49 AM
Hey...just had something happen for the first time, and what a pisser!

Seems the new recording didn't cover the old footage completely. Instead the old footage and new footage are showing as interlaced wide horizontal bands. Every other band/stripe shows the old footage, and the others show the new footage. Any idea what caused this?

I just added a new Light Wave Mini Mount to my XL-1, and since I've also added the Equalizer, I had to tilt it out slightly away from my light. I remember reading in the Mini Mount text something about keeping the mic cable vertical, otherwise it would mess up the "stereo image." My cable isn't exactly vertical, but it's more vertical than horizontal.

Is that what this is all about? If so...how in the heck does the angle of the mic cable affect the stereo image?

Baffled.

Chris Hurd
November 9th, 2001, 10:03 AM
"The stereo image..." these are Les Drever's words here, and I'll explain what he meant.

Before Les passed away last year, he used to talk about audio the way a lot of us talk about video. Audio to him was an "image," just not a visual one... an aural image, if you will.

Les wanted you to keep the mic vertical in order to maintain the left channel recording audio from the left, and the right channel recording audio from the right (this is the stereo *aural* image).

If you mount the mic off of vertical axis, with the cable pointing out to the right instead of the top, then the left channel is recording audio from above and the right channel records audio from below (usually picking up a lot of lens motor noise in the process).

Now if you mount the mic with the cable pointing *down* then you've completely reversed the stereo aural image... the left channel now picks up sound from the right and vice versa.

This is what Les was getting at.

Unfortunately John, it has nothing to do with your recording problem... try running a head cleaning tape for a few seconds. Also, I re-use tapes for personal purposes only, *never* for critical, paying jobs. Tape is the least expensive link in the whole chain of production; don't re-use it for important video.

Hope this helps,

John Locke
November 9th, 2001, 11:35 AM
Thanks, Chris. The reference to "stereo image" really threw me. Your explanation has helped me to see the light...so to speak.

As for the used tape...you're absolutely right. Here I'll lay down a wad o' cash for an accessory without thinking twice, then turn around and try to save pennies by reusing tapes. Don't know what I was thinking there. Thanks for the needed wakeup call.

Adrian Douglas
November 11th, 2001, 08:09 AM
John,

I had the same problem with my camera. Big ole black horizontal lines. I cleaned the heads, a number of times, it got better, for about 30 secs, then big ole black lines again. I got the lines on brand new never used tapes, so I sent it to Canon for a service and they fixed the problem, something to do with the heads.

Looking forward to reading the book, thanks.

Adam Wakely
November 13th, 2001, 07:23 PM
I took apart my XL1 microphone and re-connected it in reverse.
Then it was able to be upside-down with no cable strain and still have the correct stereo image(due to the "isolator" system).