By John Siskin
 Lance, B&W, 5:1 Hard Light The higher ratios look better in Black &White than color © John H. Siskin All rights reserved |
There are two separate things that digital cameras meter: continuous light quantity and light color. Since strobes are not continuous camera meters don’t read them. In teaching classes here at BetterPhoto.com® I keep trying to find ways to say that when you use strobes you need to control your exposure manually. When you use a strobe meter you get a response that tells you how to make a middle density, but it doesn’t tell you how to make it look right. There is no automatic way to make it look right, only the application of brains can do that. When I make a shot with strobes and a digital camera, the first thing I do is to put the camera on manual and ignore the camera meter. The only things I pay attention to are the proof image on the camera back and the histogram. These two tools tell you more than a strobe meter about your image. Let me suggest a plan for seeking the right exposure:
1) set the shutter speed to the sync speed,
2) set the aperture to your middle aperture, whatever that is on the lens you are using,
3) take a picture, it will be wrong that’s ok,
4) move the aperture dial to let in more or less light based on test exposure 1, you can look at the histogram to help determine how much to change the aperture, but the proof image should tell you if you need to change a lot or a little,
5) more test exposures and changes of light placement and light power until the strobes are right,
6) change shutter speed to balance values between existing light and strobe light, this will require more test pictures.
This same technique will work if you are mixing strobes and daylight. This was why the Polaroid bill was so high with film cameras, we used to call this using the polameter. With digital cameras these test exposures are free, so we should not be afraid to make them.
 Small Light Source Set-up Norman 200B © John H. Siskin All rights reserved |
The digital camera also meters light color. This is what the white balance is for. It is one of several ways to control color in the digital camera. For instance, if you are taking a digital image of a dramatic sunset on auto color the finished picture will probably be disappointing. If you manually set the color to the daylight preset, your camera has several presets, the sunset would have more of the color saturation you perceive. The neutral grey card allows you to set the camera to the actual color of the light. If I am doing something with more complex light color I take a shot of the grey card first, with the complex light. I will save this file and shoot my job. When I am doing the post work, I will use this first shot to balance all of the images I did in this set. The way you do this depends on the software in your camera.
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