On 17 Dec 2001, at 23:55, Stan Halpin wrote: > It may just be cleaning residue on the surface. However, it sounds like a > condition I have seen on a few 100mm/4 macros: the front lens elements come > unglued at the edge, and the resulting air gap causes a change in appearance > when looking at the front of the lens . . .
Although I'm not qualified to judge, I'd say it does look somewhat consistent with a separated cemented pair. However, the only cemented pair of elements in this lens design are interior ones (the third and fourth elements from the front). So the interference pattern would have to be shining through and just looking like it's on the outside. I suppose that's possible. I'm basing this evaluation on the diagram for "9 elements, 8 groups" on Boz's K-mount page. - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
