Its the grain you sometimes see on photographs

Thanks

It happens when you crank up the ISO (increasing the cams sensitivity to light). Some cameras are worse than others.

It can also be Azz whining about the fact that not enough people are buying Nikons...

However as people rightly say - the higher the ISO the more graininess you see in the picture, particularly if it's enlarged.

I tend to use ISO 200 in my normal daytime photography - however as the light falls, if I still want to achieve reasonable shots, and increase to 1600 is sometimes required to ensure I get satisfactory hand held shots without the inevitable camera shake brought on by longer shutter speeds...