Field-test of the Canon EF 75-300mm f/4-5.6 III USM zoom lens. The Canon EF 75-300mm f/4-5.6 III USM is the latest version to join the EOS/EF lens line-up, together with its Micro Motor 'sibling', the EF 75-300mm f/4-5.6 III (reviewed the previous issue). Just like the Mk II version, the Mk III lens also utilized the Micro USM. However, advances in lens technology allowed Canon to make huge improvements for the Mach III as compared to the previous edition. Like its Micro Motor counterpart, this lens is also ideal for shooting sports, still life, portraits, animals and candid photography. From its medium telephoto focal length of 75mm to the 300mm end, beautiful photos can be achieved with this compact zoom lens. As a low-priced, high performance and high-magnification telephoto zoom covering all the widely-used focal lengths, it is also the lightest of any lens in its class. High contrast imaging performance is attained throughout the zoom range and a new, lightweight glass material is employed in the first group, reducing the load on the AF motor, and helping to increase the focusing speed. Like its Micro Motor counterpart, the EF 75-300mm III USM lens accepts 58mm-sized filters and accessories. The EF 75-300mm III USM lens, like its previous editions, comes with a steel mount system rather than the plastic type that is common with most entry-level EOS products. The Canon EF 75-300mm f/4-5.6 III USM Zoom Lens The zoom lens at its 300mm setting Steel mount is utilized for this lens Wide, focusing ring for manual focus << Back to Main . 1 . 2 . 3 . 4 .