While doing a little research on the M* 300mm I purchased from CollinB I tripped across this amazingly abused A* 300mm (same optical configuration). Don't look if you are squeamish about the condition of your lens optics: http://forums.steves-digicams.com/attachments/pentax-lenses/147886d1264764384-test-shots-300-scratchedlens.jpeg
Here is the amazing part: Check out the images it still produced in this condition: http://forums.steves-digicams.com/pentax-lenses/165305-test-shots-300-a.html The main reason I decided to try the M* 300mm is for astrophotography. You can get away with a lot of imperfections in daylight photography, but pinpoint star images highlight every defect. The M* and A* 300mm f4 featured 3 of the front 4 lens elements made of ED glass (although marketing departments had not yet seized on the use of "ED" in the lens nomenclature). Other elements are made of high refractive glass. In fact, only two of the 8 elements are "normal" glass lens elements. For a film era lens, it is pretty highly corrected for chromatic aberration. 300mm is pushing the limit for use with the O-GPS1, and I'm not even going to attempt it until I get the Arca-Swiss p0 purchased. It may even have to wait for the purchase of a "real" equatorial mount that can respond to auto-guidance (the purchase of which is a loooong way off yet). But I couldn't resist snagging the lens when Collin offered last Friday. It should be in my hot little hands on Thursday. -- Nothing is sure but death and Pentaxes. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
