On Fri, June 27, 2008 02:15, Chris wrote: > > > There were lots of Americans and Canadians there. One young woman had a > camera like mine but was using a 500 mm telephoto to take birds (hand > held). > I?ve seen these for sale at £1000. I was jealous. I might be able to > afford > the mirror lens version from Mr Cad. I think it is called a ?Cadiotropic? > (sp) lens. Close, "Catadioptric". I was shooting with my old Spiratone 500mm f/8 on Tuesday. It's small, light, and focuses close (manually). But it's f/8. Slower really, in actual transmitted light, because the secondary mirror covers a fair bit of the aperture (an example of the real-world significance of "t-stops" in addition to "f-stops"). And I had a fair amount of trouble focusing it, too, especially if the subject wasn't in direct sun. A glass 500/4.5, or whatever exactly she was using, must be quite heavy for hand-holding! And presumably has IS, which would help a lot. -- David Dyer-Bennet, dd-b@xxxxxxxx; http://dd-b.net/ Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/ Photos: http://dd-b.net/photography/gallery/ Dragaera: http://dragaera.info
