I'm interested in a 600mm Apo Germinar. Do you know its approximate weight and cost? I bought a 300mm Apo Germinar a few years ago that I use as a long lens on 4x5 and it's great. I've been using the 240 Germinar W that i got from you on 8x10 where it performs brilliantly. I'm hoping to use it on a 7x17 camera that Richard Ritter is curently building for me. As soon as I receive it I'll try the lens-I'm keeping my fingers crossed that it will cover.