It may be a simple question: what is ISO in photography? However, the answer isn't quite so straightforward – mainly because it's a term that originated before digital imaging. So, let's rewind: what ...

ISO is the measurement of how sensitive a digital camera's sensor is to light. The speed or light-sensitivity of a digital camera's sensor is rated in ISO numbers -- the lower the number, the slower ...

Camera manufacturers increasingly like to crow about ISO ranges when launching a new camera, with high ISO numbers now reaching into the hundreds of thousands. But what do these numbers really mean?