A beginners guide to ISO Settings

Changing the ISO speed on a digital camera will adjust the amount of light sensitivity when taking a shot. Using a higher ISO setting will allow more light to enter the lens and therefore the shutter speed will be reduced. This will allow you to take shots in low light situations without using a flash. This can be beneficial when flash photography is not allowed.

On the Nikon D40X the range of ISO speeds are from 100 to 1600 with an option to use H1 which is equivalent to ISO 3200. Some cameras will allow you to use ISO 50. ISO 100 is ideal for bright sunshine whereas the higher numbers are great for diminished light. Try increasing the ISO speed one a t a time to get the perfect result.

The disadvantage to using a higher ISO speed is that images can appear grainy and therefore not such good quality Take a look at the images below, the one on the left was taken using ISO 100 and the image on the right using ISO1600, both images look pretty much the same but on closer inspection the right image is of poorer quality and contains a lot of noise making it appear grainy. If you englarge your images this will become much more apparent.