This new lens provides focal lengths the 35 mm equivalent of 22 to 35.5 mm, and is the first ultra-wide-angle zoom lens (approximately 1.6X zoom ratio) designed for use with Pentax medium-format digital cameras. Its optics consists of 17 elements in 12 groups, including two high-performance aspherical elements and two extra-low dispersion elements. In addition, the SR (Shake Reduction) mechanism has been incorporated, effectively compensating for camera shake up to approximately 3.5 shutter stops, says the company.
Advanced, multi-layer, HD lens coatings are applied to optimize light transmission and minimize reflection. Paired with this with the high grade Aero Bright Coating, Pentax says this lens delivers the dynamic, super-high-resolution images that are only made possible by medium-format DSLRs.
Eleven special seals are used to effectively prevent the penetration of dust and water into the lens interior.
The HD Pentax-DA645 28-45 mm f/4.5ED AW SR lens will be available this month for a suggested retail price of $5,249.99.