The optical design includes 16 elements in 11 groups. A new large
aperture aspherical lens and LD (Low Dispersion) lens elements deliver
exceptional resolution across the complete zoom range— combined with
stable imaging across the entire frame. The lens also corrects comatic
and transverse chromatic aberration, as well as distortion that often
crops up on other wide-angle lenses. Together with Tamron’s unique BBAR
(Broad-Band Anti-Reflection) Coating, which improves light transmission
and suppresses reflection and dispersion on the lens surface, this new
ultra-wide-angle zoom has been entirely reimagined to control flare and
ghosting. The result: clear, crisp images, every time.