Exposure meters indicate light intensity and are designed to help you get a correct exposure every time you take a photograph. When a light reading is taken the meter indicates the correct adjustments needed to the camera aperture and shutter speed settings. This sounds simple, as indeed it is, but not all subjects can be treated in a straightforward way. How would you tackle a backlit subject, a snow scene or subjects in deep shadow, for example? In such situations your exposure meter can well mislead you into giving the wrong exposure. ‘Correct‘ exposures are a matter of interpreting meter readings and applying them to the subject in hand. Read the rest of this entry »
Most modern cameras have a light meter built in. This has proved to be very popular among amateurs and professionals alike because of the speed and convenience it offers.
All exposure meters work towards the same end—to give the photographer exposure information—but the ways in which they operate vary widely. There are two basic types however: coupled and uncoupled. Examples of both systems are found in 35mm reflex and non–reflex as well as in smaller and larger format cameras. Read the rest of this entry »
Choosing the best exposure for a picture is just as important as getting the image sharp. A beautiful holiday picture on the beach is spoiled if you cannot see details of the people in the photographs—they may be too light or dark.
A correctly exposed negative or slide will have a full range of tones from deep shadows to bright highlights. Under-expose your photograph and the darker parts of the picture will contain little detail; over-expose, and the bright parts will appear all washed out and lacking in detail. Read the rest of this entry »
When you open the back of a camera to change the film, look inside and then press the shutter release. As the shutter opens the aperture can be seen beyond it. This shows more clearly if you look through the front of the lens or, on a camera with interchangeable lenses, take the lens off and look through that. Turn the aperture control and the size of the aperture will alter within the lens as you change the settings.
As the size of the aperture changes, so does the brightness of the light allowed through the lens. Aperture size, and therefore brightness, is controlled by the iris diaphragm, made up of a number of thin, interleaving blades which rotate to make the aperture larger or smaller. Making it smaller (stopping down the lens) reduces the amount of light reaching the film; increasing the size allows more light through. Read the rest of this entry »
Throughout this post, references are made to meters and their use in continuity testing of individual parts of the appliances and their connecting wires. All testing and checking for ‘open’ (not allowing for current flow) or `closed’ circuit (allowing current to flow) must be carried out using a battery-powered multimeter or test meter. Testing should never be carried out on live items under any circumstances. Appliances must be disconnected from the mains supply. Read the rest of this entry »
