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  By John Shaw
Well, if you work with panoramic or view cameras you'll want — make that "need" — a hand meter. It may come as a shock to some of us raised on 35mm SLRs, but not all cameras have exposure meters built into them. Even if you work exclusively with 35mm, there are times you might consider using a hand meter.
Let's start with reflective meters, since everyone is familiar with these and you already own one. This is the meter built into all 35mm SLRs. You point the meter — the camera in this case — at your subject and it gives you an aperture/shutter speed combination. What it doesn't do is give you the correct exposure values for a perfect picture. It might, but it might not. All reflective meters — with two exceptions which I'll mention shortly — do one thing and one thing only: they tell you the values to use to record your subject as a medium tone, regardless of the actual tonality of the subject. Have an average-toned subject, and you can fire away. Work a light or dark subject and you'll need to add or subtract light to that base meter reading. The meter always starts at a middle-tone placement, so you must add light to record a subject as a lighter tone, take light away to record as a darker tone. Here's a widely used chart for the amount of light to add or subtract (in stop increments): EXTREMELY LIGHT +2 light light +1 LIGHT +1 dark light + MEDIUM the metered values light dark - DARK -1 dark dark - 1 EXTREMELY DARK - 2 blackish - 2 To use this chart, just add the name of a color. For example, to record something as a light blue tone, add one stop of light to the meter reading taken of that particular area and only that area. An additional stop of light would make it record as a light, light blue. Get the idea? The exceptions to this are the evaluative matrix metering modes on current Canon and Nikon cameras. Both systems use software programs to make a judgment call as to proper exposure, and both systems suggest you never dial in any compensation when using this metering pattern. The reason is simple: you don't know what the software has done so you have no idea how much light you should add or subtract. Now let's return to my subject of hand meters. The reason I'm writing about hand meters is that a previous column was on panoramic cameras, a format I like to shoot, and I received several questions about metering. My Fuji GX617 pan has no meter whatsoever. In order to determine proper exposure I must do one of two things. Either I carry one of my Nikons, take a meter reading with it and transfer the values to the Fuji, or I use a hand meter. I've done the Nikon bit and it certainly works, but there are times when I want to pack only the pan camera and its lenses and not add any additional 35mm gear.
Remember that you still have to place tonal values. That's the negative side of all reflected light meters. They only tell you how to get middle tone, not how to get correct exposure. Always refer to that tonal chart whenever you're using a reflective meter. The plus of using a spot meter is that you can be standing in different light than your subject but still take a meter reading. For example, imagine you're in bright sun next to a rock face, but you're photographing a pattern on the shaded side of the rocks. No problem. Just meter, place your tonal values, and trip the shutter. An incident meter works in a different manner. Incident meters have a white hemispheric dome rather than a viewing lens and eyepiece. To take a meter reading you must hold the meter in the same light as your subject and point the dome back at the camera position. You're measuring the light falling on the subject. This is the same thing as taking a reflected light meter reading off a gray card held at the subject position. You take a reading and shoot at the given shutter speed/apertures values unless your subject is at one end or the other of the tonal scale. In other words, if the subject is quite dark you'll need to open up a stop from the indicated reading, or if it's very light you'll need to stop down one stop to hold detail. Seem strange? Think about this: the old "sunny -16" rule places a middle-tone subject as a middle tone on film. But you still have to stop down one stop for white subjects, and open up one stop for black subjects. An incident meter is the equivalent, in any light, of "sunny -16." The joy of incident meters is that you don't have to worry about subject tonality except for the extremes. Since more things are average than un-average, you can usually just take a meter reading with an incident meter and shoot. But if you're using any filter you've got to allow for it, and there is no way to take a reading through a filter with an incident meter. So here's that bugbear, the polarizer. Add a polarizer to a lens and it's effectively a one-stop ND filter if you see no polarization effect at all. At maximum polarization (right angle to the sun's axis, that is) one additional stop of light is lost. When you use an incident meter you must remember to open up, but how much do you open up when you're using a polarizer to determine the glare off wet leaves on an overcast day? One stop? One and a half? For 35mm shooters there are a couple of situations where a separate meter is "handy," so to speak. When you're working on landscapes, at times you might not want to change your composition to take a meter reading. A spot meter could be useful here. If you're working animals with a long lens, and you're in the same light as the critters, then taking an incident reading with the meter pointed back over your shoulder is a quick way to get correct exposure. I often check
There are a number of good meters on the market. Pentax, Gossen, Sekonic, and Minolta are the major brands, and I would stick with one of these. The digital models are far more rugged than the older style with swinging needle. Some models I have used and recommend are:
Questions and Answers 
John Shaw will answer
readers' questions in his bi-monthly column regarding equipment and
photography techniques in the field. He can be contacted via e-mail at
this address: johnshaw@photosafaris.com.
Due to the anticipated volume of
inquiries John cannot answer questions individually, but he will cover a
wide range of topics within each column. The new columns will come on-line
May 1, July 1 and
September 1. We look forward to hearing from you. |
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Joseph Van Os Photo Safaris, Inc. P.O. Box 655, Vashon Island, Washington USA 98070 Phone: (206) 463-5383 Fax: (206) 463-5484 Email: info@photosafaris.com Copyright © 2008, Joseph Van Os Photo Safaris, Inc. |