Canon 55-250mm IS STM lens preview: Is this tele zoom an ideal complement to the Canon 18-55mm IS STM kit lens?

Billed as the "perfect companion" to the Canon 70D, SL1 and T5i, Canon has announced a new long-zoom telephoto lens, the EF-S 55-250mm f/4-5.6 IS STM. This lens is the successor to the EF-S 55-250mm f/4-5.6 IS II lens, which featured Canon's gear-driven DC motor focusing system. This new model marks the sixth lens to utilize Canon's Stepping Motor (STM) focusing system, which as we've seen on other lenses, provides fast yet extremely quiet autofocus. Popular HD-DSLRs, like Canon's upcoming 70D, will benefit from the STM focusing as it will vastly reduce the risk of picking up AF motor noise in the sound captured during video recording.

As for specs, the new 55-250mm STM lens is very similar to its predecessor, with identical focal lengths and the same variable f/4-5.6 aperture. Canon stated that the previous model had a 4-stop image stabilization correction, while they tell us this new lens is only good for 3.5 stops. The focusing system is also fully compatible with Canon's Movie Servo AF and the new Dual Pixel CMOS AF system from the 70D. Canon says this lens has an improved AF algorithm and a high-speed CPU for better autofocusing.

Optically, the new version features a single UD lens element for reducing chromatic aberration just like the older model, as well as "enhanced lens coatings" for better color rendition. The old version featured "Super Spectra Coatings," but we're not sure if the new model features these same coatings exactly. The lens features a seven-bladed circular aperture to help create soft background blur. And while it does have a slightly closer focusing distance than its predecessor at 2.79 ft. (0.85m.), it's not really a macro lens, but at 0.29x maximum magnification, it's not bad.

The EF-S 55-250mm f/4-5.6 IS STM telephoto zoom lens is scheduled to be available in late September for an estimated retail price of US$350. More details on our sister site, SLRgear.com.