Steady Hand Gets Hold On Sharper Image

July 18, 1986|By Gary Haynes, Knight-Ridder Newspapers.

The most common cause of unsharp pictures is camera movement. Although an unsteady hand is a malady that always has afflicted photographers, the condition has reached plague proportions with the advent of automatic cameras. The photographer using an automatic camera frequently just aims at the subject and lets the meter do the exposure calculations. Automatic cameras--or adjustable cameras set on automatic--achieve proper exposure by varying either aperture opening or shutter speed.

In low-light situations, the shutter speed that the meter selects to expose the film properly is simply too slow for the camera to be held steady in the hands. Also, modern cameras tend to be light and small, and the lighter and smaller a camera is, the more difficult it is to hold steady by hand.

(Some professional photographers try to increase the weight and steadiness of their cameras by attaching steel plates to the bottoms.)

Here are some tips for keeping the camera steady during exposure. First, use the highest shutter speed possible, consistent with the result you want. Second, squeeze, don`t punch, the shutter release button. A camera can be stabilized somewhat if the photographer wraps the camera strap around his wrist and pulls it tight against his shoulder while pressing the camera itself firmly against his cheek.

Few people can hand-hold a camera steadily for exposures of less than 1/

60th second. For pictures requiring a slower shutter speed, a tripod should be used.

Movement by the subject being photographed is another common problem. As shutter speeds decrease, there is greater risk of subject movement blurring the photo, even if the camera is held steady. A higher shutter speed can reduce or eliminate the blur. The effect can be controlled by a fast shutter, which, in effect, ``freezes`` a moving object.

The amount of blurring in a photograph is not determined by how fast the object is moving. What matters is how far the image travels across the film while the shutter is open. That is why there is less blurring, using the same shutter speed, of an object traveling toward the camera than of the same object traveling at right angles to the camera.