Here is a tip for photographers doing doing photoshoots with models:
Always Use Manual Exposure Control
What I do is use an incident light meter with a dome. I have a Minolta Autometer IV F which I have used for about 15 or 20 years. Set it to ambient mode and take an incident exposure reading in front of the model with the dome facing the camera. Also meter behind the model to see what the hairlight reads. Pick an f/stop to get the required depth of field. Then set it the f/stop and shutter speed on the camera which is set to Manual Mode (M).
If you try to use one of the automatic exposure control like Aperature Priority Mode (A) you only set the f/stop on the lens. Then the autoexposure computer in the camera sets the shutter speed. The problem is every exposure will be a little different speed (1/125, 1/90, 1/75, 1/140, etc.). This is because dark and light areas are slightly different in each image and the autoexposure program doesn’t know that the lighting hasn’t changed. You will notice this in postproduction when every image needs a different exposure adjustment.
If you don’t have an incident light meter you can use a gray card and a reflective meter. This is ok for studio wotk, but it is too much trouble on location. Just buy an incident light meter like the one I have. The general principle is if the light and subject hasn’t changed, the exposure doesn’t have to change with every shot.
If you are shooting outdoors using the sun and sky as your light sources, you should constantly check the exposure because the light changes whenever the sun goes behind a cloud, etc. Wear the meter around your neck so it is always handy. If you ever worked on a motion picture shoot, the Director of Photography (DP) is the guy running around with the lightmeter. Lighting is his primary job and the light meter is his primary tool.
Exposure is one of a photographer’s principle creative controls. Don’t delegate that important job to a dumb computer program.
