When photography isn't the only thing on your mind, a built-in winder can free you to think of more pressing concerns.

Photographer: Scott A.Carmichael KINSA/KODAK Photo Contest

When you finish a roll of film, rewind it immediately. Then if you accidentally open the camera, you won't expose the film. Be sure to wind the end of the film all the way into the magazine so that you don't mistakenly reload it later, thinking it was unexposed film.

As you take your pictures, you'll probably have to adjust focus or exposure settings or modes for some unusual situations. Suppose you go from distant shots of a road race to a close-up of a car refueling nearby. For the distant action shots, you'll probably want to use the servo or continuous focusing mode to track action. For the close-ups, the single-shot mode will be more convenient. As soon as you're through making the close-ups, readjust your focus setting so that you'll be ready for action again. By the same token, you may want to switch exposure modes from a depth mode for the close-ups to a stop-action mode for the racing shots.

When you find an especially good subject, take at least two or three pictures of it. This will give you a choice of viewpoint, pose, expression, or composition, as well as insurance in case one of the negatives or slides gets damaged.

Autowinders are a standard feature on many 35 mm cameras. For SLR cameras without an autowinder, you can attach a motor drive to the bottom of the camera. Both built-in winders and accessory motor drives perform the same function: they advance the film to the next frame and cock the shutter after each exposure. The chief difference between winders and motor drives is speed. Autowinders advance the film one or two frames per second, while some motor drives run film as quickly as eight frames per second-far faster than your thumb could do it.

Autowinders let you take a series of pictures of fast-action subjects, such as sports or parades. An autowinder is also great for photographing the ever-changing opportunities for candid pictures of children, pets, or people. For informal portraits, an autowinder will help you avoid missing fleeting expressions or sudden gestures.

Some built-in winders and most motor drives offer you the choice of two modes: single-frame advance and continuous advance. In the single-frame mode, you press the shutter and release it for each picture you take. The camera won't fire a second time until you release the shutter button. In the continuous-firing mode, the motor will advance and fire the camera as long as you hold the shutter button down. The latter mode excels for fast action, like sports, but at three frames-per-second, you can go through a 24-exposure roll of film in only eight seconds!

In addition to advancing the film and readying the camera for the next exposure, both autowinders and motor drives are usually capable of performing other tasks, including auto-film loading and auto rewinding.

Autowinders also simplify close-up photography, especially when shooting live subjects like insects or small animals. Since these subjects move almost continuously, you have to keep them properly framed in the viewfinder and sharply focused, which is much more difficult to achieve if you are continually pulling the camera away from your eye as you cock the shutter.

With an SLR camera, one minor problem is that when the reflex mirror flips up to let light reach the film, it briefly cuts off your view through the viewfinder. When you are shooting several frames per second, the viewfinder will be blocked for much of the picture sequence. Composition and focusing becomes a bit tricky. With direct-optical viewfinders, you'll get a continuous view of the subject because the viewing lens and the taking lens are separate.

Finally, be aware that when you use a built-in flash, the continuous- advance mode may not function because the flash needs a longer time to recharge than the motor will allow.