Q. Why do some pictures sing while others fall flat?

A. Many pictures fail because nothing happens. The subject isn't doing anything.

Family pet pictures often fall into this category. A straight-up shot of Rover is okay if you just want a record of his likeness, but it may not be interesting to others. To get their attention add some action. Have Rover leap in the air or fetch a stick, or talk to him and catch that "funny" expression.

The same goes for the cat. Instead of picturing her reclining haughtily, get her moving. She could be looking into a fishbowl (watch out for the fish), playing with a ball or a roll of string. Or make a noise that would get her attention - always be ready for that lion-like yawn.

People also benefit from this kind of treatment. Unless it's a fantastic character portrait, you're better off having your model do something, something he would do naturally. A stamp collector examining his prize item, a homemaker cooking, a golfer swinging, a skier sliding down on his skis - or pants.

Watch TV commercials, they're loaded with ideas for action pictures.

Even inanimate subjects have to do something. A building can sit beside a curving road, be silhouetted against a dramatic sky, show welcome with blazing lights or rejection with vacant black windows.

Landscapes also have to do something - project a mood or a feeling. Watch for the play of light: front light flattens, sidelight brings out shapes and backlight dramatizes. Use rain, snow or wind to give a different look. A wide-angle lens spreads out the view; a telephoto constricts it.

On the other hand, don't overdo your pictures by including too much. Simplify by selective focus and throw out that busy background. Sharpen up on the center of interest, be it a face or a figure, and let the rest go.

Move in and out of peripheral detail and competing subjects. If four kids are on the beach, three of them looking seaward and the fourth homeward, move in and out the one or the other three for a better composition.

For posed groups, use a unifying "everybody look at the same spot" viewpoint. For action groups, wait until "all eyes are on the ball."

Another way that picture lose their punch is poor technique. The two chief technical offenses are lack of sharpness caused by inaccurate focusing or camera movement, and using a fast, grainy film when a finer-grain, slower film would do.

Fuzziness can be corrected by focusing exactly on your subject and holding the camera steady or using a tripod.

Graininess is unavoidable if you need the speed. But if you don't, you're better off within the speed limit of the slower films. Most pros work on this principle.