Pentax DA* 60-250mm f4 ED SDM Lens
Pentax DA 60-250mm f/4 ED SDM Lens enables shooting of focal lengths from medium telephoto to super telephoto. Its wide zoom range enables you to capture the desired scene, from bust shot portraits to sports and stage photography. ED glass is used to correct the chromatic aberration and provide high sharpness. The open F value does not change over the entire zoom range for providing a lens that is easy to use and provides high delineation performance. The lens is designed with a dust-resistant and drip-proof construction and SDM mechanism (AF based on ultrasonic motor in lens). When the lens is attached to an 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-compatible digital SLR camera, AF operation can be performed by the motor in the camera body (Note 2).
Focal length equivalent to 92mm to 383mm in 35mm film format
The high-magnification 4.2X telephoto zoom covers an expansive telephoto range, making it ideal for shooting of sports scenes and portraits.
ED (extra-low dispersion)
Two ED (extra-low dispersion) glass lenses are used for correcting the chromatic aberration. The field curvature aberration at all focal lengths is also reduced in the zoom mechanism, and a nonlinear movement system is used for providing stable imaging performance.
Open F value that remains unchanged even when zooming
The optical system is a fixed F value type where the open F value does not change over the entire zoom range for enhanced ease of operation.
Hybrid AF mechanism
This lens uses a hybrid AF mechanism that supports both "SDM" using the ultrasonic motor in the lens for enabling quiet and smooth autofocus operation and the conventional autofocus operation using the camera's internal motor.
Dust-resistant and drip-proof construction
The various lens components have been sealed for enabling a dust-resistant and drip-proof construction that prevents the entry of water and dust into the lens.
Quick-Shift Focus System
If you turn the focus ring after focusing by the AF, focusing instantly switches to the manual focus. This enables smooth focusing operations without the need for a switching operation.
SP (super protect) coating
A special coating is used on the front lens for repelling water and oils. This enables any water and oils on the lens to be easily removed for effective protection of the lens surface.
Design developed specifically for digital SLR cameras
This design has been optimized for digital image characteristics to minimize ghosting and flare. Also, the image circle is tailored specifically to the size of the imaging elements for allowing a compact, lightweight body size for a large-aperture lens.