Oops - sorry! My mistake. The screen on my OM 4 looks grittier to my eye than the D300's, hence my confusion. Probably just because it is bigger.
But the bottom line for me is that on a DSLR, presumably owing to the smaller viewfinder, the DOF preview is harder for me to use.
aha...the answer to this and every other DSLR dillemma is:
Buy a Nikon D3x - or die!

