The Difficulties of Camera Noise
on the Set

by John Cunningham 1997

The first step in getting a clean movie soundtrack was to try--as far as possible--to record it clean to begin with. However problems frequently arose on the set because the movie cameras themselves (not to mention all those technicians running around) were pretty noisy. Of course different cameras made different amounts of noise. [Take classic 3-strip Technicolor for example: the camera was so noisy that it required a huge "blimp" (sound-proof housing), and the actual camera plus the blimp weighed a ton (figuratively speaking). It is this huge square blimp that you see in the on-the-set production stills from classic Technicolor films. (Look at some of the behind-the-scenes still from GONE WITH THE WIND (1939), for example.)] Some cameras were "unblimped" (sometimes called "MOS" cameras) and they were intended to be used on shots during which sound was not being recorded (like action shots, second unit material, extreme long shots, etc). They sounded like "pea thrashers" and that's what they were often called behind their backs. ("We'll just grab this take with the pea thrasher!")

Other cameras are (nowadays) "self-blimped" cameras and are much, much more quiet. Though they too make a certain amount of noise which can become a problem when the mic must be close to the camera. In this case there are several possible remedies which may be used (or usually, a combination thereof): a different microphone position, technique, or microphone, can be chosen which will eliminate (or lessen) the offensive noise; a "barney" can be placed over the camera (a barney is a heavy blanket-like cover for the magazine portion of the camera which helps greatly to cut down on the noise); the sound recordist can equalize the sound to help eliminate camera noise (although this can get you into deeper trouble); the shot could be adjusted to be shot with a longer lens which would place the camera further away from the scene; the lines can be retaken as "wild lines" (these are line readings by the actors which are re-recorded by sound only, usually immediately after the take, without the camera running); etc, etc, etc--there are lots of tricks, depending upon the situation. Many a take has been shot with the camera and cameraman under a heavy blanket!

It is not usually so much that they "delete" the camera noise from the soundtrack as it is that they try to work very hard to NOT record camera noise to start with. However, sometimes equalization, notch-filtering, and similar tricks must be done after the fact in a situation where there are really noisy tracks.

If the original tracks are deemed unusable, then, as a last resort, the dialogue may be re-recorded in a process that is known today as ADR (automated dialogue replacement) (formerly known as "looping"). This technique was once very commonplace in American films, but nowadays is rather frowned upon, and is usually used only for a relatively few line here or there which, for one reason or another, need to be made more intelligible (or need to be changed).

The advent of quieter and self-blimped cameras along with advances in ultra-directional microphone technology has mostly eliminated the need for lengthy post-production replacement of dialogue (although there are always exceptions to this, notably low budget productions which just do not have the time in the shooting schedule to permit obtaining more perfect production tracks).

Thankfully, the modern Panavision camera equipment has evolved to the point to which it is remarkably quiet; the modern Arriflex models have come a long, long way. Many filmmakers used to complain horribly about the Arriflex BL3s and BL4s. I read an article in which Sidney Pollack complained bitterly about camera noise in the dialogue tracks in OUT OF AFRICA because the cinematographer, David Watkin, insisted on using Arri equipment because (at that time) Arri had sharper lenses than those available for Panavision equipment.

Careful micing techniques and thoughtful camera placement go the farthest in solving these production problems.

The real trick for the motion picture sound folks shooting on location is consistency. A single scene is usually shot over a period of several hours (sometimes MANY hours; sometimes DAYS) and the ambient sounds usually change at least somewhat (and often greatly) during that time. This is why post-production sound is such a big job---all these sounds must be evened out and matched up before (and/or during) the final mix, so that the sound perspective and presence doesn't change every time the shot does!

© 1997 John Cunningham

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