What Is ISO in Photography?

Understanding ISO

ISO refers to your camera sensor’s sensitivity to light. A low ISO value like 100 or 200 works best in bright conditions and produces clean images. A high ISO such as 1600 or 3200 increases sensitivity and helps in low-light environments.

ISO and Exposure

ISO is one part of the exposure triangle, together with shutter speed and aperture. Increasing ISO makes photos brighter without changing other settings. However, very high ISO levels can introduce noise and reduce image quality.

Choosing the Right ISO

For the best image quality, always use the lowest ISO possible. Increase ISO only when you cannot achieve proper exposure with your current aperture or shutter speed. Proper ISO balance helps maintain clean and natural-looking photos.