Ah yeah I know which button it is now, yeah I don't use it because it changes the shutter speed to slower or faster which I can do anyway if I need to in order to get a correct exposure. By the way, this test shot was taken kist about 10 minutes ago to see how much noise there is :
http://farm3.staticflickr.com/2831/9774865393_8e20fdcae3_o.jpg
I took it using ISO800, I used the 'Natural' preset and set all parameters to default '0' meaning the middle position, even sharpness which I normally have set to full. Does this look ok for noise? I can see noise but i'm right in thinking that noise shows up the lower the amount of light there is right? So at night noise would show up a lot more than say, 1pm in the afternoon on a sunny day. Also, I was under the understanding that no-one with half a brain uses an ISO above 200 in the daytime, I always thought ISO400 and above were only used normally at night or in low light. Amd I right in thinking now, that people DO use ISO800 and 1600 in the daytime to get the shutter speed they need?