i got one of these from ebay. optics were suppose perfect. but the focus does not work. lens has a small amount of fungus. i killed it and you can just barely see it now. focus is fixed, it was frozen grease. works great now. i'm returning it because i already have this lens. i bought it because i was fairly certain about the focus problem and i was right. as i said, it's got a small amount of fungus in it. it is still a superb lens and what little there is in NO way affects the image quality. this lenses is one of pentax's finest, without a doubt.. if someone here would like to get this for $45usd delivered then i need to know soon as it's going back to the seller monday. i would not even offer this if what i said was in anyway wrong. you don't like it, send it back and i'll send you the shipping $$ to do it.. i've just been SO DAMN impressed with my other one.. the macros i've posted recently. that lense has as much dead fungus in it.. i think there are 2 of this lense on ebay right now for $70+ before shipping.. i would not offer this unless i already had a copy..