Digital cameras use a sensor to capture the image produced by the lens. The sensitivity of the sensor can be varied according to the international standard ISO 12232:2006, commonly referred to simply as “ISO”, which is analogous to the ISO speed designation found on film stock. A setting of ISO 200 is twice as sensitive as ISO 100 and will result in an image twice as bright (assuming all other parameters remaining equal). Higher ISO numbers incur a penalty in the form of increased image noise or grain. Cameras able to shoot at high ISO settings with minimal noise exhibit superior low-light performance.
