Nikon D300 Complete Manual page 285

two stops. Do your images look as if they were shot at ISO
800 when you run a correction on them in post processing?
I'm betting that, yes, they do. Just like with the other Nikon
DSLRs, I see an almost direct one-to-one correspondence
between results from underexposure and higher ISO use on
the D300.
As you increase ISO you'll find that colors tend to lose a bit of
their punch (e.g. get "muddy"), and contrast is lowered. At the
extreme, it can result in the equivalent of a 2-bit or higher
reduction in individual color values, which is easily seen in
images. HI 1.0 shows obviously less color saturation, but the
effects begin as early as ISO 1600.
When the D300 first was announced, I was asked many times
about whether it was usable for indoor sports. As I did with
the D2x, D200, and S5, I decided to test the question. During
one of my weekly basketball games, I brought my D300 and
set it to essentially the worst possible scenario (ambient
lighting on a bad day, Auto white balance, ISO 3200, High
ISO noise reduction set to Low). I was at f/2.8 at 1/1000,
which should be fine for stopping action (note the ball).
Here's the best result (at 100%) that I could pull from the NEF
file:
Thom Hogan's Complete Guide to the Nikon D300
V1.02
Page 285