For amateur use, most modern cameras sport a built-in exposure meter. Most point-and-shoot cameras, also called ‘compacts’, offer no choices in exposure control. Some refined models give a selection of modes like landscapes, people, sports and close-ups. One can select what is being photographed and program it accordingly.
SLR cameras today are very sophisticated and offer a wide variety in terms of exposure control. They offer several metering systems and a variety of exposure modes. Due to stiff competition in the camera market, cameras are coming out with an endless variety of metering systems.
The center-weighted meter concentrates on 60% of the viewfinder’s central area and gives the reading based on that area. For a very long time this variety dominated the scene and even today no camera comes without it. It works well for a wide variety of situations. Camera manufactures also provide an exposure lock which allows photographers to point the camera at a spot outside the scene, lock the exposure and point it back at the shooting scene.
A multi-segment meter on the other hand is a more intelligent system because it reads the whole scene and after computer calculations gives the suitable reading for the scene as a whole. Center-weighted readings ignore marginal segments but a multi-segment meter is more considerate to the whole scene. For example, if the upper left one-third portion is dominated by the sun, the centre-weighted meter would underexpose rest of the scene.
The spot meter is a very specialized method in which only a tiny little portion (5%) of the scene is read. It does not take into account the rest of the scene. A spot meter becomes very handy in specialized situations where the reading of a very small part is extremely crucial. For example, the face of a tiger in a dense forest would be critical, especially if the tiger is sitting in the sun and the forest is in deep shade. A spot meter would do the job ideally in a tricky situation like this, where center-weighted metering would grossly overexpose the scene.
In reflected readings, the meter reads the exposure is of the overall light and reading is taken from the subject, pointing the meter towards the camera. In spot reading one can select the angle of spot reading needed, depending upon the criticality of the area of the scene. In flash meter reading, readings are made by fixing flashguns and the aperture stops are given indicating suitable aperture for the strength of the flashgun being used. This is used by professional photographers mainly in situations requiring the use of several flashguns.