Summary: I purchased this lens when I had my D80. It stuck with me on my D7000, and my D600. It's an excellent lens to use for portraits because you can really isolate your subject from the background. The low light capabilities are great, and auto focus in dark locations is much better than 3rd party lens manufacturers. I highly recommend this lens for individuals who really want to get creative with depth of field and have a solid workhorse for walking around.
Summary: I bought this lens two weeks ago, have done two shoots with it at 1.4 in daylight & artificial light as well. I can proudly say that the D.O.F you get from this lens, DOESN'T COMPARE WITH ALL THE OTHERS OUT THERE. Reason? 1. "TACT SHARP QUALITY/FOCUSING", 2. "SOFT, CREAMY D.O.F", 3. "IDEAL/PERFECT CHOICE FOR D-MOVIES". I own a D800, Its ISO RANGE and the MAXIMUM APPERTURE of this lens, its just PHENOMENOL.
Summary: I upgraded from Nikon 50m f/1.8 here is what I've noticed: *About 1/2 stop more light from f/1.4 to f/1.8 *The depth of field is not very noticeable from f/1.4 to f/1.8 *The sharpness and clarity of the lens vs the 55mm f/1.8 is huge! I LOVED my old 1.8, but now this is so much sharper.