Guy's, Here's another of my oldie memories. Back in the mid-to-late 80's, Tamron made a 135mm, f/2.5 adaptall2 lens that absolutely superb. I did some research into this lens and found an obscure promo brochures that made the statement that this lens was constructed using "Rare Earth" glass. (HAH) I had already assumed such. Sadly, I dropped the lens into a lake at the point where the water was in excess of 100 feet deep! Just a bit more than I'd try to snorkel down in to look for it. Not that I didn't give it more than a passing thought. I've looked for another one on the internet for several years now and just missed on at KEH by about 20 minutes and it was sold for 49.00 in excellent condition! Art Tafil