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A speciffic use auto exposure system for video and film.
Sure, we've got auto exposure, auto flash, and variable intensity lighting, lets combine them! This is nothing new on the hardware front really, except perhaps for the interface box, but none the less It an idea I like. Well I would wouldn't I?
Basicaly you start with an auto-apeture film or video
camera with TTL (through the lens) metering, Then you interface it to a computer controlled dimmer connected to your lights. The system adjusts apeture, AND sends out a control signal to the dimmer control box, to automaticaly adjust the brightness of the lights. The system would be calibrated to produce exposure as the average human eye would. The system might also include an external light metering device as well as the TTL meter, Allowing, with proper lighting location a complelty natural scene illumination level with no input from the videographer or cameraman.
Sure a mid-brightness light and a lens with a wide aperature range can provide "correct" exposure in most situations, but what I'm getting at here is emulating the "exposure" that the human eye perceives. I see this being popular with documentary, news and low-budget drama producers.
For example: Say you have a very dark hallway, but your lens only opens up to f4 and you are operating at an ISO equivilency of 200; the system will automaticaly bring the light up JUST enough to compensate for the slow lens and ISO, maintaining the "exposure" as the human eye would percieve it. Alternately you could preset an aperature for depth of field and have it adjust the light on the fly for propper illumination. If coupled with an auto focus system or focus position sensor it could also adust brightness for subject distance.
3 exposures at different levels, later number-crunched together [loonquawl, May 25 2009]
||nobody ever voted or commented on this idea? Was the user being shunned? Voodoo death hex? I shudder at the thought.
||The boils down to replacing the mechanism of camera-person shouting to lights-person by something automatic. The attempt at capturing nearer to the human dynamic range is better realized by HDR ([link]).