Digital cameras, of course, do not use film – but the same ISO scale that was used for film is used to control your EOS camera’s sensitivity to light. As the ISO is increased, your sensor becomes more sensitive to light – and this helps you get that fast-enough shutter speed you may need in low light when hand-holding.
This makes ISO a powerful tool, helping you to get sharp shots in a variety of lighting conditions. You’ll find ISO is a simple set ofbase sensitivity of Canon EOS cameras is ISO100. But this can be increased by pressing the ISO button and then rotating the correct dial (on some cameras, ISO is changed through the red menu). The scale is simple, in that doubling the ISO number doubles the sensitivity of the sensor – for instance, increasing the ISO from 100 to 200 means you can use a shutter speed that’s twice as fast, such as 1/250 sec increasing to 1/500 sec.
