(From Canon lens literature) To leverage the unique, new shooting functions of the EOS Rebel T4i, such as EOS Full HD Movie with continuous AF, Canon is introducing two new unique lenses, the new EF-S 18-135mm ƒ/3.5-5.6 IS STM lens and new EF 40mm ƒ/2.8 STM lens. Both new STM lenses includes Canon’s new Stepping Motor technology, which allows the lenses to smoothly and silently focus, and when used in combination with Canon’s new EOS Rebel T4i Movie Servo AF feature, achieve continuous AF while recording video. The new stepping motor technology in both lenses quietly focuses allowing the EOS Rebel T4i’s stereo microphone to only record the sounds of the scene being shot.
The new EF 40mm ƒ/2.8 STM lens offers an ultra-slim, lightweight design that helps photographers avoid overwhelming their subjects with a large lens and to remain discreet in sensitive shooting situations without compromising performance. The “pancake-style” lens boasts an aperture of ƒ/2.8 making it an ideal lens for capturing portrait stills or stunning video. The lens is under an inch thick when attached, making it easy to carry and fit conveniently into a purse or pocket.
