ISO is a setting in your camera that will make the photo brighter or darker in camera. Increasing your ISO number will give you a brighter photo and reducing the ISO number will give you a darker photo. The lower your ISO is, the longer your shutterspeed is and the better quality your photo will be.

So, why do we have to adjust the ISO for every photo? Why don’t we adjust the camera to the highest ISO number? Increasing the ISO number too high will increase digital noise in your photos and losing quality. Digital noise is a visual distortion on a photograph, those tiny coloured pixels we see in the photograph is digital noise. In terms of film photography noise is also known as grain. This means that increasing your ISO numbers when not necessary might ruin the photo.