ISO in Digital Photography. In Digital Photography ISO measures the sensitivity of the image sensor. The same principles apply as in film photography – the lower the number the less sensitive your camera is to light and the finer the grain.PHOTOGRAPHY What is ISO?What is ISO? A camera's sensitivity to light explained, and how to use itstructuresxx/123RFIn photography, making sense of some of the jargon can be a daunting task. That said, it’s key to knowing your way around your camera and taking excellent photos. One of the most confusing settings is ISO, which is one of the three factors of exposure along with shutter speed and aperture. Fortunately for you, we’ve put together this simple explanation to help you better understand what happens when you change your camera’s ISO and how it will affect your images.
As you can see these pictures demonstrate ISO.
Auto ISO 100 200 400
800 1600 3200 6400
Here I have taken my pictures outside to capture natural daylight and to experiment with ISO settings.