Announced just prior to Photokina 2014, the SP 15-30mm f/2.8 Di VC USD is a newly-designed ultra-wide-angle zoom lens for full-frame D-SLRs. It boasts of a fast f/2.8 aperture throughout its zoom range, along with Vibration Compensation (VC), the world’s fi rst in this focal length category. Th e lens is available in Canon, Nikon and Sony mounts, but the Sony mount does not incorporate VC as Sony D-SLRs include built-in image stabilisation. The lens we received for review had a Nikon mount. Let’s see how this new baby fares on our test bench…
Design & Build Quality
The SP 15-30mm f/2.8 Di VC USD has its outer body made from engineering plastic and is reasonably well-made, though quite heavy (1040 g without both end caps) due to the large glass elements used for the ‘fast’ lens. The front element is bulbous and hence you cannot use any ‘protection filter’. The lens comes with its own petalshaped hood, which is actually a hood within a hood – at 30mm setting of the zoom lens, the front element of the lens withdraws along with the inner hood and at the 15mm setting, the front element extends back to its original position when both the hoods coincide. The hood is a permanent fixture of the lens itself. A well-made plastic lens cap covers the front element when not in use. The lens mount is made from metal. The lens is made in Japan.
The SP 15-30mm f/2.8 Di VC USD zoom lens is constructed with 18 elements in 13 groups that include a XGM (eXpanded Glass Molded Aspherical) element placed in the front group and several LD (Low Dispersion) glass elements within the remaining elements. These special elements control geometrical and lateral colour distortion, enabling the lens to provide edge-to-edge sharpness and superior image quality throughout the zoom range. Tamron’s BBAR (Broadwhich Band Anti-Refl ection) coating is applied to certain lens elements to allow uniform transmission of critical bandwidths, while flare and ghosting, typically observed in ultra-wide-angle lenses, is controlled by the use of eBAND (Extended Bandwidth & Angular Dependency) coating. Since the front element has a convex profile (which does not allow a protective filter to be attached), it is coated with a water and dust repelling chemical (fluorine), which further facilitates easy cleaning of the front element should the need arise. The lens offers Vibration Compensation (Tamron’s way of saying image stabilisation) but Tamron does not specify the number of stops advantage. An Ultra Sonic Drive (USD) speeds up autofocus. Manual override is possible.
The zoom ring, which is rubberised for a better grip, is marked at 15, 18, 20, 24 and 30mm settings. The manual focus ring is also rubberised but is not as wide as the zoom ring and is towards the lens mount. A plastic window covers the distance scale in meters as well as in feet. On the left of the lens is the AF/MF (Focus Selector) switch but manual override is possible even during autofocus. Below this is the VC (Vibration Compensation) switch. A rubber gasket helps prevent dust/moisture from entering the lens at the lens-body coupling. The Nikon mount lens has eight contacts that couple with the camera body contacts.
The Tamron SP 15-30mm f/2.8 Di VC USD zoom lens comes with ‘SILKYPIX Developer Studio for Tamron’ – a Raw image processing soft ware.