Re: HD light metering -- need advice

One of the reasons it is nearly impossible to use a light meter to determine exposure with video is that it's almost impossible to determine the "true" ASA of any video camera. And, the relative ASA in low light will be different from the relative ASA in bright light. You can try to reverse engineer this: with a waveform monitor, set the iris to the correct exposure. Then with your meter measure the light and find the ASA that gives you the same f/stop. But, because the relative ASA changes in low light, this is mostly a waste of time. The only use I find for light meters on a video shoot is to get consistency.

Zebras are you invaluable friend when it comes to judging exposure with video. Especially when you have no monitors, no waveform, no engineer. Set the zebras to 70. Then place a "normal" Caucasian in front of the camera. Adjust iris until there is just a whisper of zebra on the hot spot (usually the nose or forehead, sometimes a part of the cheek). And you are set. If your subject is particularly dark-skinned, borrow a Caucasian to set iris.

Shooting landscapes you may be better off setting the zebras to 100. When parts of clouds show some zebra you are probably OK. But here it's more difficult. Due to the narrow range of exposure with most video cameras, usually you have to sacrifice either shadow or highlights to get a decent exposure. Depends on the framing, the look, the time of day, etc.

Rick Wise
director of photography
San Francisco Bay Area
and part-time instructor lighting and camera
grad school, SF Academy of Art University/Film and Video
http://www.RickWiseDP.com
http://www.linkedin.com/in/rwise
email: Rick@RickWiseDP.com