ISO Settings

The ISO speed affects the shutter speed / aperture combinations that you use to obtain correct exposure.
a digital camera's light meter warns you there is not enough light to correctly expose a scene, the options are to  use the on camera flash, slow the shutter down or have a higher ISO. if the ISO is increased sensitivity allows you to obtain a correctly exposed picture, However all this increase in sensitivity does not come without drawbacks, your image will appear more digitally noisy and so is less likely to be able to be printed to a large size format.


below are 3 examples of different ISO settings to show how low, medium and high settings can affect a image dramatically.


on the first image the ISO value is 200 and you can see limited amounts of content within the scene, below on the second image the ISO value is 800 and you can begin to see more background content, and finally on the 3rd image you can see as the value of ISO is 1,600 we can see a wall in the distance however it appears very noisy and if enlarged would make for a poor quality print.