Field-test of the Canon EF 28-105mm f/3.5-4.5 USM zoom lens. When the EOS System was introduced in 1987, there was an EF 28-70mm f/3.5-4.5 AFD zoom lens offered among the EF lenses line-up. Two years later, the EF 28-70mm f/3.5-4.5 Mk II version was introduced. Both of these lenses were compact and lightweight. The AF operations were also fast despite the use of the earlier AFD (Arch Form Drive) motors. When Ring USM with FT-M (Full Time Manual) focusing was made available for the first time with reasonably-priced EF zoom lenses in 1990 starting with the EF 35-135mm f/4-5.6 USM (issue 34), EF 70-210mm f/3.5-4.5 USM and EF 100-300mm f/4.5-5.6 USM (issue 46), it was just a matter of time before Canon upgraded the EF 28-70mm AFD Mk II with a version employing the FT-M USM feature. Upgrade the lens featuring USM technology Canon did, but instead of offering EOS users the same focal lengths as the AFD version, the new zoom had the coverage extended to 28-105mm! And the new version is none other than the Canon EF 28-105mm f/3.5-4.5 USM zoom lens. When this lens is set to its 28mm position, the overall length (75mm) is about the same as the EF 28-70mm Mk II AFD type. But when the focal length is set to its 105mm position, the lens is extended. Canon EF 28-105mm f/3.5-4.5 USM The setting at the 105mm position Unlike the AFD version, which employs the internal zooming system, hence keeping the overall length of the lens the same regardless of focal length positions, the EF 28-105mm f/3.5-4.5 USM uses the conventional method for its zoom control mechanism. However, it did use the internal mechanism for its focusing system and the there is no change whenever the lens is focused at its closest focusing distance or at infinity. Angle-of-views from 28mm to 105mm focal lengths At 28mm At 35mm     At 50mm At 70mm     At 105mm Weighing only 375 grams, it is easy to carry around. Its two-step lens extension prevents the lens from obstructing the built-in flash's coverage of EOS models like the entry-level EOS 300 (Rebel 2000), EOS 88 (EOS 3000) to the mid-range versions like the EOS 50/50E (Elan II/IIe) and EOS 5 (EOS A2/A2E). << Back to Main . 1 . 2 . 3 .