dbdors wrote (editred for space):
Most EOS cameras can maintain autofocus to F5.6, The EOS 3 can autofocus down to F8 (cant remember what the 1V will do, but I assume it will also go to F8, anyone know what the 1D and 1DS will do?). In either case the 100-400 with Canon 2X is smaller than F8 at all focal lenghts. The lens becomes a 200-400/F9-11. With a Canon 1.4X it becomes a 140-560/F6.3-8, so you could have autofocus with the EOS 3 at all focal lenghts. ---------------------------------------------------------------------------- ------------------- Darrell, The EOS1v is can also autofocus stopped down as far as F8, not sure on the 1Ds. The newer TC 1.4x and 2x from Tamron, Kenko, and Sigma all provide the same capability in terms of reporting the correct aperture when used and for lenses that have a maximum aperture smaller than F8 (as you stated above a 200-400mm F9-11 with 2x) will automatically disengage the AF. Peter K * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
