On Thu, 27 Oct 2005 19:50:39 -0700, "Joseph Chamberlain, DDS" <drjchamberlain@xxxxxxxxxxxxx> wrote/replied to: > >3.2 - The 100-400mm lens offers the obvious benefit of improved telephoto >zoom range. However, the 70-200mm lenses could be fitted with the Extender >EF 2x II to transform them into 140-400mm lenses. I've been told that in >doing so the maximum aperture is reduced and I should be careful since the >minimum aperture compatible with autofocus is f/5.6. I have the 100-400 and love it. I hate having to use extenders, but do use a 1.4x on my 100-400. Depends what you're shooting but for things like birds you never have too much focal length. The 100-400 is a bit heavy but so is the 70-200. The DO lens is a novelty that is more compact, but the question remains why? The first lens you mentioned, the new one would be an excellent choice of an all around lens. Personally I have the 28-135 IS and love that lens too. Much cheaper alternative with a good range and sharp image. If you told us what you'll be shooting that would help. -- Jim Davis, Owner, Eastern Beaver Company: http://easternbeaver.com/ Motorcycle Relay Kits - Powerlet, Posi-Lock I'm a BMW rider and enthusiast.
