Guess focusing

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Guess focusing was the most common way of focusing a camera for many years. Photographers had to estimate the distance to the subject themselves, and set the focusing ring or focusing lever accordingly. They were somewhat assisted by the depth of field scale. Usually the aperture was not too big, typically f/4 as a maximum. It is not possible to guess the distance with enough precision for larger apertures or greater focal lengths.

These cameras were usually more expensive than those with fixed focus, but cheaper than the rangefinder or reflex type.

A variant was scale focusing, used on cheaper cameras, targeted to people who would not take the trouble to guess a distance in meters or feet. Symbols on the focusing ring (usually one person, a group of people and a mountain) indicated the most probable setting for the picture depending on the subject.

This range of camera has evolved to become the point and shoot camera, equipped with an autofocus device, consisting of an infrared light emitted by the camera and reflected by the subject. Photographers do not have to guess the distance themselves, and of course the operation is faster.