Hello, I want to ask you. I have the option to buy a used Canon 300 mm 2.8 IS made in 1999. On the surface has a few minor scratches but the optics are clean scratched. Test photos looked beautiful razor sharp. But my personal impression of him was such that the lens is quite professional too slow refocusing from minimum distance to infinity. If you focus so precisely but I still have too feel that this refocusing on longer distances is slow ... It also seemed to me that somehow sharpening ring goes harder, but it can be just my wrong impression because it's my first lens canon 300 mm 2.8 IS and I do not give it out to compare
May be the USM already worn?
May be the USM already worn?