What is exposure? Camera exposure explained

Exposure refers to how much light enters the camera when you shoot a picture.

If there is optimal exposure, the amount of light that enters is just right (which is subjective according to the effect you want to achieve).

If there is over-exposure (too much exposure), your image will have too much light in it and is likely to appear very bright and white. This is sometimes said to be "washed out". With extreme over-exposure the whole thing can appear just white. Sometimes you want a picture to be more white than it actually is for effect, or to lose details on purpose.

If there is under-exposure your image will have too little light in it and will likely appear very dark. With extreme under-exposure the shot can be virtually completely black. Sometimes a photographer desires darkness to get a certain look.

Factors that effect exposure

Exposure depends on two main factors:

1.) Aperture - The larger the aperture, the more light can enter the camera and the more exposed the picture will be. Large aperture gives high exposure and small aperture gives lower exposure.

2.) Shutter Speed - This refers to how long you leave the shutter open to capture the light before you take a shot. If there is a really fast shutter speed there is little time for light to enter and the picture appears less exposed. At longer (slow) shutter speeds there is more time for light to enter and the image has greater exposure.

Adjusting the shutter speed affects what's known as "exposure time", and this tool can be used not only to manipulate how bright or  dark a shot is, but it can also be used to capture movement in unusual ways. When the shutter is open for a long time to record a shot, if the shot is moving in this time, it captures the motion blurs brilliantly. Conversely, if you have a short shutter speed, it creates a sharp shot of the thing in motion - like a sharp snapshot of a moment in time with no motion blurs.

3.) ISO - This is an artificial manipulation of how sensitive your camera is to light for a particular shot.