Table of Contents
Advertisement
Concepts in Photography
How the aperture setting, shutter speed,
and ISO sensitivity control exposure
The aperture setting, shutter speed, and ISO sensitivity are closely
interconnected in photography. The aperture setting controls the opening
that regulates the light that enters the camera, while the shutter speed
determines the length of time that light is allowed to enter. ISO sensitivity
determines the speed at which the film reacts to light. Together, these
three aspects are described as the triangle of exposure.
A change in shutter speed, aperture value, or ISO sensitivity can be offset
by adjustments to the others to maintain the amount of light. The results,
however, change according to the settings. For example, shutter speed is
useful in expressing movement, aperture can control the depth of field,
and ISO sensitivity can control the graininess of a photo.
Settings
Wide aperture
Aperture
= more light
value
Narrow aperture
= less light
Results
Wide = shallow depth of field
Narrow = deep depth of field
Settings
Fast speed
= less light
Shutter speed
Slow speed
= more light
High sensitivity
= more sensitive to light
ISO sensitivity
Low sensitivity
= less sensitive to light
Results
Fast = still
Slow = blurry
High = more grainy
Low = less grainy
21
Advertisement
Table of Contents
