Originally Posted by dcstep
... and I'll never understand that need. I get really sweet bokeh at f/4.
However, I DO have the 500mm f/4 and if I couldn't afford that I'd be considering a 70-200mm f/2.8 with the 1.4x and 2.0x TCs. Either that or the 300/f2.8 with the TCs.
Here's something interesting to do. Go to Flickr or Smug Mug or any searchable image database that has lens specs and EXIF. Most images taken with f/2.8 lens are shot at f/4 and smaller apertures.
I saw a review on the nikon 70-200 2.8 current version, and they were saying that the DOF isn't as narrow as one would expect. The review said it was because nikon chose to substitute less vignetting at wide open for less DOF.