In message ,
RichA wrote:

Some reviewers criticize the Nikon's for not having a
100 ISO setting, they start at 200. This is supposedly
because Nikon sensors in the cameras that feature this
are more sensitive so that a Nikon at f4 and 1/250 of a
second has an ISO of 200 while another camera will be at
100. Is this true? IF so, there should be less noise and
more dynamic range in the Nikon set at 200 ISO than another
DSLR set at 200 ISO.

Take the same shot with the same lens; a t-mount with manual aperture,
mounted on a tripod (in non-changing lighting), set multiple cameras to
"ISO 200" with he same shutter speed, and fire away!
--


John P Sheehy