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Shooting In A Loud Car Yard

Busy highway off to one side.

Any thoughts on erecting some kind of audio barrier? Like a big scrim in a frame?

We have shot there before, found radio mike with Lavalier (neck)to be effective (boom inconsistent...) although it needs -20dB pad.

He's never too far from camera as he can't read the cards anymore and autocue is too small - even in the biggest size. OF course he won't wear his glasses, Silly!

John Hollands
Producer
Sydney


John Hollands writes :

>Shooting a presenter in a loud car yard...Busy Highway off to one >side...Any thoughts on erecting some kind of audio barrier? Like a big >scrim in a frame?

There's really nothing you could build that will silence a highway at that close range.

Maybe you could charter two or three buses for a few hours and park them (with no gaps between them) between the action and the highway. That might help some.

You could also use a cardioid (directional) Lavalier (i.e., Audio-Technica 831B) with your wireless system, which will tend to exclude noise coming from the sides.... but CAVEAT :

A) They're larger than omnidirectional Lavs.

B) They must be aimed EXACTLY at the talent's mouth -- not over his shoulder or away from him.

C) They'll also be more susceptible to wind noise, clothing rub, etc., so use them carefully.

Use a windscreen, of course. Most importantly, use a high-pass (low cut) filter, which will further mitigate wind and friction/handling problems, as well as the highway traffic itself.

If you can stage the action so they highway is behind the talent, that will also help.

Dan Drasin
Producer/DP
Marin County, CA


Shooting a presenter in a loud car yard...busy highway
>Any thoughts on erecting some kind of audio barrier?

Odds are that the sound is fairly omnidirectional and you'll have a hard time creating any audio shade. Dan's ideas (and caveats) are good. Depending on several factors, you could also try something like a cardioid version of the Countryman E6 Earset. That costs about $500 (variability depends on connector) I think, so is a lot to spend on one gig. But they do get used successfully by on-air talent at some NASCAR broadcasts...

http://www.countryman.com/

If that's too much money, you could try a standard cardioid lav and hair mic him. That might work. Or you could find an office/shed on the yard, shoot in there, and just show the yard through a window.

Man, it's going to be tough. Might be worth hauling along a mixer with race-car or airport experience or something...

Jim Feeley
POV Media
http://www.povmedia.com


Loop it.

Sam Wells


Loop it.

That is an option, but I was guessing this was an industrial/corporate gig. I figured cost, talent's vocal chops, time, and other factors might make that path more difficult. But ya.

John, let us know what you end up doing and how well it worked...

Jim Feeley
POV Media


Sam Wells writes :

>Loop it.

That's probably the best advice of all. It may cost you less... or more...but will probably give you the best results. You could try it first with the cardioid Lavalier, and if that doesn't work well enough just use the original track as a guide track for your ADR. Also, record at least 30 to 60 seconds of whatever ambience you want to mix with your clean (looped) dialogue.

Dan Drasin
Producer/DP
Marin County, CA


Has anyone tried that noise cancellation trick where you mix a microphone pointed at the noise source out of phase with your talent's microphone?

It's supposed to work like those helicopter headphones you flick a switch on and the noise goes way down but I've never seen anyone try this on a film set.

Bruce Douglas, DP
Sao Paulo, Brazil


Has anyone tried that noise cancellation trick where you mix a >microphone pointed at the noise source out of phase with your talent's >microphone?

One of the sound guys I work with has experimented with this... We tried it in a few situations. How well it works is hard to predict - often, unfortunately, it doesn't do much at all.

Situations where it seems to work - if you can place the "cancellation" mic at the same distance from the noise source as the talent mic, but in a position where it won't pick up the talent... and if the room acoustics are pretty dead, then it seems to work all right. Unfortunately in real life situations, it's often hard to achieve this.

In a test, we achieved almost complete cancellation of a TV in a hotel room beside a person speaking... But trying it on location in an industrial site with lots of loud fans and motors produced negligible results.

In the TV experiment, we could literally hear the effect kick in as we moved the cancellation mic around.... But in the industrial site, the noise was coming from everywhere, not from a single point source, and we weren't able to find a "sweet spot" that significantly helped.

Maybe others have had more luck and experience with this technique...But from my experience, it's not something you can depend on, certainly without testing each situation in advance.

George Hupka
Director/DP
Downstream Pictures
Saskatoon, Canada


Bruce Douglas writes:

>Has anyone tried that noise cancellation trick where you mix a >microphone pointed at the noise source out of phase with your talent's >microphone?

The lower the frequency of the noise, the more neutral the ambient acoustics and the more fine-tunable the relationship between the mics, the better this technique can work. But low-frequency noise can often be more easily and effectively removed with simple high-pass (low-cut) filtration.

If you have a panel of presenters seated at a table behind an even number of mics, you can wire half of them out of phase to cancel some general low-frequency ambient noise. But then you've got to keep an equal number of in-phase and out-of-phase mics open (and at the same level) at once, which you may not want to do.

>It's supposed to work like those helicopter headphones you flick a >switch on and the noise goes way down

Those work as well as they do because the relationship between the noise-pickup mics and the reproducer element is close, fixed and predictable.

Dan Drasin
Producer/DP
Marin County, CA




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