Photography can be defined as the art, science and practice of creating various durable images by recording the light and other types of electromagnetic radiation. This can be done either electronically by using an image sensor or it can be done chemically by using a very light sensitive material. An example of a light sensitive material is a photographic film. A lens is very commonly used to focus all the light that is emitted or reflected from the objects into a very real image or also a light sensitive surface that is present inside a camera.
Camera and its controls
Photography is typically done by using a good camera. There are many controls in a camera that are extremely useful in the long run. Some important controls are as below.
Focus
This is the position of an object that is viewed or also an adjustment of an optical device that is necessary in order to produce a very clear image. This can either be in focus or out of focus.
Aperture
An aperture is an adjustment of the opening lens and it is measured by a number that is called the f-number. This aperture controls the high amount of light that is passed through the lens.
Shutter speed
The adjustment of speed of a shutter is done in order to control the amount of time that is taken when an imaging medium is exposed to any light for each of the exposures. A shutter speed can also be used to control the amount of light that can strike the image of the plane.
White balance
On all digital cameras, an electronic compensation for the color temperature that is associated with a given set of lighting conditions ensures that a white light is easily registered in the same way on an imaging chip. Thus all the colors in a frame will appear in a natural manner.
Metering
The measurement of an exposure is done so that all shadows and highlights are exposed strictly according to the wishes of a photographer. Most of the modern cameras and are also set on an automatic basis. Before an automatic exposure, a correct exposure is easily accomplished with the help of a separate device called the light metering device.
Film speed
This is traditionally used to tell the cameras that the film speed of all the selected films on a film camera, the film speed numbers are also employed on the modern digital cameras as an indication of the gain of a particular system.
The autofocus point
On various cameras, the selection of a particular point in an imaging frame upon which a system of auto focus will attempt to focus is always present. Also many reflex cameras that have a single lens always feature multiple points for auto focus in a particular viewfinder.
There are various other elements in an imaging device. These elements include the focal length, filters, inherent sensitivity and a recording material. The resolution is always measured in grains and pixels.