"John A. Stovall" wrote:

On Mon, 14 Nov 2005 17:35:06 +0000 (UTC), Paul J Gans
wrote:

wrote:
What are canon EF-S lenses? What is the difference between EF-S & EF lenses?
Are EF-S optimized for digital cameras, to take into account the 1.6x
conversion factor on small-framed sensors?

Yes. EF-S lenses are optimized for digital cameras. They
are mechanically set up so that they are difficult or
impossible to mount on full-frame cameras.


You seem to forget there are Full Frame Digital cameras.

The reason they are made not to mount on FF Canon bodies is they are a
compromise for small sensors.

Not exactly. They are designed for the APS-C sensor. There is no
compromise involved.

Colin D.