On-set noises have caused problems for sound recordists for years, but digital brings new ones to deal with. Most, if not all HD camcorders, and many HD cameras, are fitted with fans to cool the internal electronics – some have more than one fan. These fans are high-pitched and quite loud, and switch on and off as the camera requires more or less cooling. In the case of cam- corders, these fans seem to switch on and off irrespective of whether the machine is recording or not, so it is quite possible that the fans will switch on in the middle of a take. A colleague who recently recorded an HD feature film, told me that on his project they largely got away with these noises because the project had a lot of loudly spoken and leary characters, ‘subtle’ acting was not a requirement. He also told me, however, that had he been required to record a period piece on HD, then he would have been concerned as to the viability of achieving any usable dialogue when shooting in smaller, intimate, interior locations.
A simple solution would be to let the camera’s cooling fan run all the time except when the camera is recording, and thus stop the unwanted
noise during that recording time. It is unlikely that the camera would be recording for so long that the internals would overheat, and there could be steps put in place to ensure that the camera will come to no harm, whilst least affecting the sound recording. Not only do the fans in the cameras annoy, but the scanner (rotating head drum) can cause similar unwelcome noises as well. A solution to both of the above could be to use a thick padded leather camera cover (known in film circles as a Barney or blimp). Though these undoubtedly reduce the camera noise to a far more acceptable level, they often block the airflow around the camera body causing the camera to run even hotter and need even more fanning! There are stories of HD cameras overheating in such conditions.
Another source of undesirable on-set noise is the ‘video village’, as it is often referred to. The video village is the area where one or more, generally large, HD monitors or plasma screens are set up for tech checks and similar. It is usually in this area that technical video ‘stuff’ gets done – master sync and timecode generation, master (if no camcorder) and/or back-up HD video recording, down conversion to standard definition video for instant on-set playback (which generally involves delaying audio to match the down converted pictures), frame grabs for later matching of shot sizes or lighting for SFX etc.
A whole host of essential processes might be done in the video village, but there is the inevitable catch that, yet again, most of the equipment used in this place relies on internal fanning to keep it cool. The average video village is not a quiet place, so the best thing you can do is to move it as far away (acoustically) from the shooting area as possible. This involves an amount of decision making as to whether you move the village further away from the shooting area to enable sensible sound recording, or keep it closer for communication and practicalities of cable runs etc. A goodly number of people will gather around the monitors at the video village. These people are all human (generally) and invariably the more people that gather, the more shuffling, coughing and other acoustic noises will be made – another good reason for moving the village a little further away from the set.
If you are shooting at a ‘real’ location – a house or similar – then it is often possible (essential?) to build the village on a different floor of the building, or in a room far enough away for the noise not to be a nuisance. Exterior set-ups are generally less of a problem as there is usually enough urban ambient noise to cover that of the village. A common problem is when you are shooting in a studio with a number of adjacent sets built within one sound stage, and the obvious thing to do is to find somewhere fairly central to build the video village, to ease cable runs and communications etc. This is possibly the worst thing to do for the sound department – the noise of a central video village can often be heard on all of the adjacent sets. Possible solutions might be to use a nearby room for the village, or a Portacabin or a similar demountable structure in a corner of the studio – anything really that
might create a solid barrier to stop the unwanted technical noises finding their way to the set. Note that the dedicated recorder recommended for use with the Thomson Viper system is called The Director’s Friend. When I attended a demo I counted four large fans whirring away in the back of it – Director’s Friend perhaps, but no friend of the sound department for sure!
It is most often the case that the DoP on a HD shoot will want or need an HD monitor close to the camera or set such that he or she might be able to check the lighting and exposure. The larger the monitor then generally the more or larger and/or louder the fans it will contain. It might be wise to give some thought to ways of reducing the noises made by these monitors (polystyrene box built around the back or similar).
There is another source of on-set noise which is peculiar to 24p shoots and is caused by any HMI lighting that may be in use. Most modern HMI ballasts allow the lights to be run in one of two different modes – flicker free and silent, where flicker free is rather noisier (high pitched buzzes and squeals at anywhere from about 6 kHz upwards). Because of the frame rate of a 24p camera, most often HMI lights can only be used in the noisier flicker free mode so may well add to the sound recordist’s worries.