Canon has introduced a new stepper motor lens, a 55-250mm telephoto zoom lens with a maximum aperture of f/4.5-5.6. It replaces the previous 55-250mm (non STM) lens.
It is the first telephoto lens to use STM technology, which is designed for smooth and near-silent autofocus for movie recording, although it can be a little slower than USM (ultra sonic motor) focusing.
The lens offers fluid continuous focus tracking when shooting movies of moving subjects, and STM also makes for cleaner transitions when making focus shifts from one subject to another.
A new design means that a 3.5 stop advantage can be gained from optical image stabilisation technology, when compared to non-IS models.
The lens includes 15 elements arranged in 12 groups, with an improved focusing distance of just 0.85m throughout its zoom range. An Electro Magnetic Diaphragm (EMD) with circular aperture has been designed to give photographers fine control over aperture and smooth, blurred backgrounds. Chromatic aberration is tackled by an Ultra-low Dispersion (UD) lens.
A non-rotating front element is included in this design, which is useful when a filter is attached to the front of the lens.
Weighing just 375g (13oz), the Canon lens is designed to appeal to travelling and holidaying photographers looking to cover a wide focal range.
The new Canon 55-250mm f/4-5.6 telephoto lens price is £349.99 (approx US$545/AU$606) with availability from late September.