Originally posted by frank Seems some 'dusty' lenses are actually foggy ones on the rear group. It's actaully pretty easy to clean. I've opened up mine 'cause I thought there were some funny stuff inside my copy too, but actually those funny stuff was on the out surface of the lens.
The rear glass is a two element group which is screwed on to the barrel. Just open up the mount plate (be careful, don't lose the A contact which is a four piece assembly), then turn the rear group anti clockwise with something like this:
Thanks for the info on the fogging. I think many of the things that make people want to throw away their lenses are actually serviceable. A professional cleaning is $50-100. I figure, if servicing is too expensive for the lens, I may as well try to open the thing up; there's nothing to lose, and it is fun to see how the lens works.
For these lenses, I would rather have a professional have a go at it, though, especially since I lack the nice tool set you have (Japanese standard screw drivers is as sophisticated as I get).
BTW, still 11 copies available, though they may be of less quality than the others.