Delivering an effective focal length range of 28-620mm (35mm equivalent) on APS-C DSLRs (varies slightly in Canon mounts), the moisture-resistant Tamron 18-400mm all-in-one 22.2X zoom is a mere 12.14cm (4.8 inches) long and weighs just 705g (24.9 oz). An HLD (High/Low torque-modulated Drive) is designed to save power and enables smooth AF operation, plus allows for a smaller AF module that helps reduce lens size. A new barrel design, which includes distribution of complex movement across three cams, insures smooth zooming. The lens also offers built-in vibration compensation of 2.5EV and, to expand its capabilities even further, a minimum focusing distance of 0.45m (17.7 inches).