Rob Brigham wrote: > > I think you are confusing this with 'Aspherical' - shape of lenses to > correct aberrations. > The Sigma APO refers to a lens coating rather than lens design.
You're probably right about the aspherical, but Sigma identifies the number of APO elements in their lenses, so I'm guessing that coating alone is not quite right. Unless only a few elements get "special" coating? Everytime I talk about the technical stuff, I feel like a 13 year old boy discussing women. Grin. -Lon - 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 .
