smc PENTAX-DA★16-50mmF2.8ED AL[IF] SDM

Featuring sharp resolution, deep contrast, and clear and brilliant color reproduction
This Star lens series brings out the best quality in your digital images by superior imaging performance with low distortion at the super wide end and a brightness of F2.8 over the entire zoom range.

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Built-in ultrasonic motor (SDM mechanism)
This lens features a compact ultrasonic motor for enabling an internal AF mechanism (SDM mechanism). It also includes a brake function for easy speed and position control to enable smooth and precise AF operation.
When the lens is attached to a SDM-compatible digital SLR camera, operation automatically switches to the AF by the SDM mechanism (Note 1). When the lens is attached to a non-SDM digital SLR camera, AF operation can be performed by the motor in the camera body (Note 2).

Note 1: SDM-compatible PENTAX digital SLR cameras include the K-7, K20D, K200D, K-ｘ, K-m, K10D (firmware version 1.30 or later), and K100D Super. If you have K10D with firmware version 1.20 or earlier, download the compatible firmware from this website and install it to your camera. Note 2: Non-SDM K100D and istD series cameras automatically switch over to AF operation using the internal camera motor.