That element is bad, but not bad enough to destroy sharpness. I bet there is certainly some loss in contrast on that lens. Also night shots or anything with point light sources in the frame would be very problematic IMO.
On Tue, Oct 1, 2013 at 9:26 AM, Darren Addy <[email protected]> wrote: > 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. -- 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.
