what is iso? generally speaking it is an international organization for standardization. but when speaking on photographic terms it is a bit more specific than that. iso refers to the sensitivity of the sensor to light. and is measured in a range of numbers. it's an important number and factor to be aware of and every time i step out with my camera, one of the first decisions i make is in regards to my iso. what does it need to be set to? when shooting film (which i pretty much do all of the time), i select my iso when i select the film that i'm shooting. my go-to film of choice? portra 400. what's the iso on portra 400? easy, it's 400! when i'm shooting with my digital camera i change my iso based on the amount of available light. here are some basic recommendations for iso settings:
200 -- outdoors, sun shine, sunny day
400 -- outdoors/indoors, a good amount of available light
800 -- indoors or darker lit areas
1600 -- dark gymnasiums, indoor sporting events, some births or other darker indoor activities
3200 -- this is the speed that i use when shooting births. very limited available light.
a few other things to keep in mind when adjusting your iso... higher iso's increase the grain in an image. also, if you're struggling to get the right exposure with your shutter and aperture and you need your shutter to be faster than the amount of available light will allow--change your iso! increasing the sensitivity of the sensor will provide you more flexibility with your exposure and shutter!!