Above is an example of an image with a fair amount of digital noise. You can particularly see the grain over the groomsman’s black coat. I believe this was shot at 3200 ISO on the 5D. (Not all cameras are equal when it comes to ISO – for example, our 5D has quite a bit at 3200 ISO while our 5D Mark II’s don’t reach as much noise until they go up to 6400 ISO or higher)
Above is another example of a higher ISO (this was taken without flash). You can really see some of the grain at the top of the image where the tent is in the background. Though, in this photograph, we don’t feel the grain takes away from the overall impact.
Above is an example of a photograph with very little noise (taken at 100 ISO). Note that even in the shadows there really isn’t any grain or noise showing up.