I got about a month ago that lens. It is quite rare and mechanically in very fine condition. One of lenses had pretty bad fungus growth and there was quite much something greasy (helicoid lube?) on the same lens too. Cleaning was pretty difficult (dish soap+water > isopropyl alcohol>isopropyl alcohol&ultrasound cleaner>24 h soak in acetone) and one lens did lose some of multicoating in the process/fungus has eaten it. This is normal so far. I removed the 3 lenses from head and the back was as it was. I think that I put everything back correctly but the lens focuses like there would be a extension tube. That is, it focuses from something like 50 cm to one meter. Image quality isn't bad but not great: (this is 100% crop) The front lenses were 2 menisculus lenses and one double convex and they don't simply fit any other way in. As it is 135mm lens few millimeters don't have this kind of effect (extension tube of something like several cm might cause this). Any ideas?