The ‘Exposure Triangle’ is a term common to photographic discussions because three functions of your camera affect the way it captures that image. The analogy might better be that of a camera tripod because the three legs are adjusted to fit the specific photographic needs at the time. 42nd St Photo takes a look at one side of that ‘triangle’—ISO.
ISO is the understood short form for the International Organization for Standardization, an attempt to regulate world-wide proprietary, industrial, and commercial standards. In photographic film the ISO (or ASA) numbers indicate how sensitive the film is to light; 100, 400, 800, etc. with the 100 film being much less sensitive than the 800 film to the light available and the resulting image containing finer grains as a result. When the image is enlarged the size of the grains composing the image become very evident.
In a digital camera the ISO is understood to be the sensitivity of the sensor to light. Your eyes are sensitive to light and adjust automatically, in bright sunlight you might put on sunglasses to adjust even further. Just as putting on those sunglasses allows you to see better, adjusting the ISO allows you to take better pictures in certain situations.
Generally, a 100 ISO is acceptable and will give crisp photographs. A higher ISO setting will result in ‘noise’…the graininess in the picture caused by the speckles of pixels that did not record correctly. There are times you may want that high ISO setting; a low light or no-flash setting like a concert or a candlelit room where a flash would destroy the mood. You compensate for potential graininess with the other legs of that tripod/triangle, aperture and shutter speed.
The cameras at 42nd St Photo give you an option in ISO settings, from automatic-don’t-think-about-it to the ability to adjust all the facets of your equipment and get the image you are shooting for.