Exposure – “ex-pos-ure”
- The state of being exposed to contact with something.
- An act or instance of being uncovered or unprotected.
What is exposure?
Exposure in both amateur/professional photography and videography is the measurement of the total amount of light allowed to hit the photographic medium (either a piece of photographic film or digital CMOS/CCD sensor) while you take a photograph.
For photography a single cycle of the shutter is deemed as the exposure of the image. This exposure can be controlled by changing the aperture of the lens, the ISO and the shutter speed. Increase either one of these three and the exposure value with increase. Decrease one and the value decreases. Obviously if the resulting exposure is a sum of these three factors, you can get the same resulting value by changing all three in different combinations.
This is in essence the art of photography – getting a required exposure in an image by controlling the light hitting the film medium by controlling it with the camera. Effects on changing the aperture, changing the ISO and changing shutter speed can be found in previous posts, and changing each one affects the final look of your final exposed image.