Canon EF Lenses

Canon EF 28-105mm f/4-5.6 USM Zoom Lens

This incredible lens is the smallest and lightest in its class. It's totally new optically, with an Aspherical element to keep the quality up and the size down. Even more noteworthy is an entirely new Micro USM, that's about half the length of previous designs -- with the same focusing power and performance.

Features like circular diaphragm blades (for natural backgrounds) and internal focusing (the front element never rotates) round out this great new lens.

Canon EF 28-105mm f/4-5.6 USM

Features and Specs | Large Image

Key Features of the Canon EF 28-105mm f/4-5.6 USM Zoom Lens

Ultrasonic Motor: Powered by Canon's exclusive Micro Ultrasonic (USM) motor for autofocusing, the EF 28-105mm f/4-5.6 USM is silent in operation and very quick to focus. There is virtually no whining noise as the lens focuses to distract the subject or draw attention to the photographer. Most important for the photographer in the field, the motor draws minimal power so the camera batteries last longer.
One Aspherical Lens Element: Wide-angle lenses and fast normal focal-length lenses often suffer from an optical problem -- spherical aberration -- which causes an overall softening and optical "smearing" of the image. Canon has developed four different manufacturing technologies to produce Aspherical lens elements, which combat this problem. Aspherical optics, which have an extremely precise variable curvature of one or both sides of a lens element, also allow more compact lens designs and permit lighter lenses with fewer elements.
Circular Aperture: This Canon lens features a circular apertures diapragm unit, which uses curved aperture blades to provide for a more rounded opening as the lens is stopped down. It's especially effective at rendering out-of-focus background highlights as natural rounded shapes. Offers a more pleasing out-of-focus image.
Inner Focusing and Rear Focusing: An inner focusing lens has the focusing lens group(s) in front of the diaphragm, while a rear focusing lens has the focusing lens group(s) behind the diaphragm. Both focusing systems allow the focusing lens group to be small. This minimizes the load on the actuator which drives the autofocus. In turn, the AF speed is faster. The whole optical system can also be made more compact. Also, since the lens does not rotate during focusing, the effects of a circular polarizing filter or gelatin filter remain intact.
EF Lens Mount: In designing the EF lens mount, Canon engineers gave photographers a lot more than simply a way to quickly attach an interchangeable lens to a camera body. With the elimination of mechanical connections and the incorporation of an electronic interface between the camera and lens, Canon cameras have greater flexibility with regard to incorporating future technologies and future system upgrades. This fact has already been proven with a vast increase in AF speed, increased functionality such as predictive autofocus systems found in EOS cameras, auto-aperture tilt-shift (TS-E) lenses, the use of ultrasonic motors and the development of the Image Stabilizer lens.
The fully electronic mount system has none of the shock, operational noise, abrasion, play, lubrication requirements, slow response, diminished precision caused by lever operation, or design restrictions related to linkage mechanisms used to transfer data. Furthermore, operation and reliability are significantly improved. And, a lens operation self-test system, using the lens' built-in microcomputer, can even warn of malfunctions through the camera's LCD readout to help ensure high reliability.

Specifications

Focal Length: 28-105mm
Maximum Aperture: 1:4-5.6
Lens Construction: 10 elements in 9 groups
Diagonal Angle of Viewn: 75º - 23º 20'
Focus Adjustment: Inner focusing system with USM
Closest Focusing Distance: 0.48m / 1.57 ft.
Zoom System: Rotating type
Filter Size: 58mm
Max. Diameter x Length: 2.6" x 2.7" / 67 x 68mm
Weight: 7.4 oz. / 210g

Canon EF Lenses
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