by Jim McGee
The Digital Rebel is the first Canon digital SLR to support a new lens mount called the EF-S. The “S” stands for short back focus. An EF-S lens has the same contacts as a standard EF lens but the rear element sits further back into the camera body, bringing it closer to the image sensor. EF-S format lenses will also reduce the size of the image circle that is projected onto the sensor.
The 1.6x factor when used with Canon’s EF 35mm lenses doesn’t represent a magnification of the image provided by the lens. But rather represents a cropping of the available image (see What’s the Big Deal About a Full-Size Chip? for a complete explanation).
The first such lens is the EF-S 18-55mm f3.5-5.6. This lens provides the equivalent coverage of a 28-90mm lens in 35mm format. It offers a circular aperture for smooth out of focus elements, internal focus, an aspherical lens element, and a minimum focus distance of just 0.9 ft (0.28m).
Another interesting feature of this lens is a new optical coating that Canon claims to minimize ghost images and flare when used with digital imaging sensors. It is compatible with extension tube EF 12II & EF 25II but it is not compatible with any of Canon’s previous or current digital cameras other than the Rebel.
Sorry 10D owners.
This lens will be available packaged in a kit with the Rebel for $999. Separate pricing for this lens is not yet available.