Digital BW, The Print

Steve Kale,
I think that what you are seeing is a blurring/distortion effect. The 
images at Nick Brandt's site have the effect of being made with an old 
Diana plastic lens toy camera or a with a tilt/shift camera or with a 
"Lens Baby" attachment. In all the above, the image is distorted on the 
edges with the center of the image in good focus. So, the effect that 
you are seeing is an in-camera effect during the taking of the image. 
To simulate the effect after the fact try any number of the "lens" 
burring effects out there for Photoshop on a selective area of the file 
(namely around the edges to leave the center in focus).

Good luck,
Hal Gage
halgage.com