DA★300mm F4 ED [IF] SDM

Best optical Performance for high-quality images

This super telephoto lens includes two ED (Extra-low Dispersion) optical elements. The second and fifth lenses use ED glass, to effectively minimize spherical and chromatic aberrations, while delivering high-resolution, fine-detailed images with rich contrast from the image’s center to its edges and minimal color bleeding at any focal length setting.

Inner focus construction
The optical system uses an inner focus construction, which is supporting the high demand to the image quality and also allows a significantly more compact design.

Supersonic AF motor (SDM)

Thanks to the incorporation of the PENTAX-original SDM autofocus system driven by a built-in supersonic motor, this zoom lens offers exceptionally smooth and quiet autofocus operation.
When mounted on an SDM-compatible PENTAX K-mount lens-interchangeable digital camera body*, the focus mode is automatically switched to SDM-assisted autofocusing to ensure dependable, flawless AF operation. 

* This lens is compatible with the K-3 Mark III, K-3II, K-3, K-5 II, K-5 II s, K-30, K-01, K-5, K-r, K-7, K-x, K-m, K20D, K200D, K100D Super and K10D camera bodies (with Ver. 1.30 or later firmware installed).
When mounted on other camera bodies, the focus mode is automatically switched to manual.