Upload & Sell: On
Jeff, Leighton, Ray, Ronny, Kevin, Tony and Reagan: thanks for your kind comments!
Tony, regarding the sharpness of the 105/1.8: I did an informal, very unscientific test of several short and fast tele-lenses and found that at medium distances all the lenses were lacking sharpness wide open.
Close up, for head-and-shoulder-portraits, I've found the 105/1.8 is just right wide open. Not "clinical" sharp, but not too soft, with a beautiful rendering of skin and hair.
edit: "tested" lenses were the "old" AF-D 85/1.4, the AF-S 85/1.8G, the 105/1.8 Ais, a converted Summicron-R 90/2 and the Ais 135/2. I would really like to know how the DC-lenses would have performed and also the 85- and 100-Zeiss-optics. The AF-S 85/1.4G is reported to be pretty good at medium distances - still have to try this one.
I currently have a 100/2 MP ZF2 rental (it's due to be shipped out tomorrow back to lens rentals) that I've been comparing to my other lenses.
In a nutshell, the claim to fame of the 100/2MP is not color rendering or (micro-)contrast, but rather it's corner to corner sharpness either wide open or stopped down. It seems to have no spherical aberration wide open (or very little at least) and thus is very sharp even wide open and gets just a bit sharper when stopped down. I tested my sample at infinity and it beats the 105/2.5 AIS handily in corner sharpness and overall contrast. I compared it to my 90/3.5CV at infinity and actually the 90CV was a hair better in sharpness across the frame with the same amount of contrast. The 100/2 MP also is very sharp up close (as is the 90/3.5CV).
I also tested my 70-200/2.8 VRII at 100mm against the 100/2 MP and found the sharpness at f/4 to be the same on my D800 except for the very far corners of the frame where the zoom tended to fall a bit short of the prime - not unexpected. This kind of behavior is backed up by photozone's test of each lens.
The DC lenses I've found to be just so-so. Specifically I found that my copy of the 135/2DC to be not sharper than my 135/2 AIS and super finicky to get to AF accurately - so why bother? I also have used the 105/2 DC and it seemed much better AF-wise, but it suffers from a bit of low contrast wide open with a lot of CA (as does the 135/2DC) although it is a bit sharper than the 135/2DC wide open (at least the copies I had). For the price you are better off with a used Zeiss 100/2.