What does ISO measure in digital photography?

ISO measures the camera’s sensitivity to light, which is a crucial aspect of digital photography. When the ISO setting is increased, the camera sensor becomes more sensitive, allowing it to capture images in lower light conditions without needing a longer exposure time. This is particularly useful in situations where lighting is poor, as increasing the ISO can help to maintain a faster shutter speed and minimize motion blur.

Understanding ISO is essential for photographers, as adjusting this setting can directly impact the quality of the image. Higher ISO values can lead to more noise or graininess in the photographs, so photographers often have to balance sensitivity with image quality. This concept emphasizes the importance of mastering ISO in order to achieve the desired results in various lighting scenarios.