The-Digital-Picture have just reviewed the new Sigma 30mm F1.4 EX DC HSM, a fast large aperture lens designed for digital SLR cameras with an APS-C sized sensor.

“Sigma’s HSM (Hypersonic Motor) internal autofocus is very nice - reasonably fast and very quiet. The quietness makes it seem even faster. The front element does not rotate and FTM (Full Time Manual) focusing is available. The manual focusing ring is smooth but somewhat stiff. The stiffness is not all bad as your hand will likely be holding the lens by/near this ring - if it turned too easily, you might product OOF (out of focus) shots. AI Servo performance including accuracy is good. “

Website: The-Digital-Picture - Sigma 30mm F1.4 EX DC HSM Review