Definition
ISO refers to the International Organization for Standardization. In terms of cameras, the ISO number refers to light sensitivity, whether for film or digital sensors, depending on camera type.
Common ISO Settings
Common ISO settings include 100, 200, 400 and 800.
Meaning
Lower ISO settings are less sensitive to light and are used for bright light situations. Higher ISO settings are more sensitive to light and are used for low-light situations, such as nighttime shots or shots taken indoors when flashes are forbidden.
Trade-Offs
One thing to keep in mind is that though higher ISO settings are more sensitive to light, the output is often grainier than the output from a lower ISO setting.
Changing ISO Settings
Most film cameras automatically change the ISO setting upon the input of film. For digital cameras, check with your camera's manual to determine how to change the ISO setting.
Article Written By Susan Berg
Based in Philadelphia, Susan Berg has more than 10 years of experience as a writer and editor. Her work has been published in both print and online media, including the "Dayton Daily News," BioZine and Wcities. Berg earned a Master of Arts in journalism from Indiana University.
