[Mike McCarty]

ISO 200 - 1,600, excellent. Why no ISO 100? Simple: the only reason for slow ISO speeds in the old days of film and in digital point-and-shoots was to get great color and no grain. I explain why compact digital cameras still need ISO 50 and 100 here. The D70 gives such great results at ISO 200 there is no need for the older, slower speeds like ISO 100, 50, 25 (Kodachrome II in the 1970s) and 10 (Kodachrome in the 1940s). If you want to use big apertures you just shoot at 1/8,000 of a second.

Julie,

The above was excerpted from the following site:

http://www.kenrockwell.com/nikon/d70.htm