The Right Shutter Speed

You must choose a shutter speed that stills both camera and subject movement. If using a tripod, a shutter speed of /l5 to 1/60 second should be adequate to stop average subject movement. If you are using electronic flash, you are locked into the flash-sync speed your camera calls for— unless you are "dragging" the shutter. Dragging the shutter means working at a slower-than-flash-sync speed to bring up the level of the ambient light. This effectively creates a balanced flash exposure with the ambient exposure.

35mm SLRs and DSLRs use a focal-plane shutter, which produces an X-sync speed for electronic flash use of V60 to 1/500 second. Using the technique of "dragging the shutter" you can shoot at any shutter speed slower than the X-sync speed and still maintain flash synchronization. If you shoot at a shutter speed faster than the X-sync speed, the flash will only partially expose the film frame.

Outdoors, you should normally choose a shutter speed faster than 1/60 second, because even a slight breeze will cause the subjects' hair to flutter, producing motion during the moment of exposure.

When handholding the camera, you should use the reciprocal of the focal length of the lens you are using for a shutter speed. For example, if using a 100mm lens, use /100 second (or the next highest equivalent shutter speed, like /l25 second) under average conditions. If you are very close to the subjects, as you might be when making a portrait of a couple, you will need to use an even faster shutter speed because of the increased image magnification. When working farther from the subject, you can revert to the shutter speed that is the reciprocal of your lens's focal length.

A great technical improvement is the development of image stabilization lenses, which correct for camera movement and allow you to shoot handheld with long lenses and slower shutter speeds. Canon and Nikon, two companies that currently offer this feature in some of their lenses, manufacture a wide variety of zooms and long focal length lenses with image stabilization. If using a zoom, for instance, which has a maximum aperture of f/4, you can still shoot handheld wide open in subdued light at 1/10 or 1/15 second and get dramatically sharp results. The benefit is that you can use the light longer in the day and still shoot at low ISO settings for fine grain. It is important to note, however, that subject movement will not be quelled with these lenses, only camera movement.

When shooting groups in motion, use a faster shutter speed and a wider lens aperture. It's more important to freeze subject movement than it is to have great depth of field for this kind of shot. If you have any question as to which speed to use, always use the next fastest speed to ensure sharpness.

Some photographers are able to handhold their cameras for impossibly long exposures, like / or / second. They practice good breathing and shooting techniques to accomplish this. With the handheld camera laid flat in the palm of your hand and your elbows in against your body, take a deep breath and hold it. Do not exhale until you've "squeezed off" the exposure. Use your spread feet like a tripod and if you are near a doorway, lean against it for additional support. Wait until the action is at its peak (all subjects except still lifes are in some state of motion) to make your exposure. I have seen the work of photographers who shoot in extremely low-light conditions come back with available-light wonders by practicing these techniques.

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