I have no first-hand experience with the lens in topic, but so far my experience with mirror lens is they are mostly soft. Of course there are differences, for example the f5.6/500 Rubinar is almost sharp (well let's say it's sharp as the Canon kit lenses :D) and f8/500 Phoenix is nowhere near to any kind of sharpness.
If you want to see a shot made with K10D and Sigma f8/600 then take a look at here: http://somaa.fpn.hu/4257.pef I think if it's for web ... it could be usefull, easy to carry solution for the budget. But if you need quality for larger prints ... forget it. Sincerelly, Timber -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
