I love prime lenses,,,I am not a professional. I work at a job that offers alot of overtime and have balanced my buget so I save and buy, I have never had any amount of vignetting to any of my shots when useing any of these. I use a 50mm f1/4, the 85mm f1/2 and the 50mm f1/2 belongs to my wife. The fifty f1/4 is light and the most versital of the set. When I put my 85mm on, it stays there and is only removed for my zooms. The 50mm f 1/4 will always be used when I want to get alittle closer and use special filters. Concerning sharpness, it is a must to control your f stop for the corners and use a tripod, if you think you can get away with hand held it is very reasonable to try as they can be very fast and sharp. You can have them all in AF and still manually change the focus, the 85mm is very easy and fast to focus, the 50mm f1/2 is alittle stiffer when manuel focus in the AF mode. All in All, I love them and would spend it seems my life savings to obtain them, for me it took a few months of extra work and they were mine one at a time., I borrow my wifes 50mm f1/2 and it is like a luxery compared to my light weight 50mm f1/4. The f1/2's are heavy with a lot of glass. For me, the 85 is a small telephoto and that's what I like, closer,, you can't beat the portrait power of it. The 50 F1/2 and the 85 f1/2 only go to f16, the 50mm f1/4 will do f22. You have to like primes, our it will be a waste of money as you will end up with your zoom back on your camera. If you like fast, they are the best for the money....
