Good sharpness for a vintage zoom, when used from 135mm to 200mm. Very good sharpness in macro mode. built to last.
Some CA and softness wide open in the 80-135mm range. Front rotates while focusing. Quite heavy. Tripod collar could have more clearence from the lens construction. Hard to disasseble for cleaning.
This is my first comment in this site and for a good reason. I think that this lens is underapreciated. Although Its optical quality is not near to new lenses, but for a price of 20-50US, it is a great bang for the buck. One of the best vintage tele zooms out there for a price of a beer-can zoom.