The company says the lens includes “the most advanced optical and mechanical designs,” an HLD (High/Low torque modulated Drive) for the AF system, and Vibration Compensation system.
A new lens barrel design utilizing three-step extensions was developed to enable the necessary elongation to produce a 22.2x zoom ratio. Compared to the conventional approach, the division into a larger number of cams ensures comfortable operation and stability while zooming, Tamron advises.
The power-saving HLD motor produces “outstanding” driving torque, and adjusts motor rotation from low to high speed to enable accurate and quiet focusing. The HLD motor takes up less space thanks to its small size and circular arc shape that allows the size of the lens to be reduced.
The electromagnetic diaphragm system, which has been a standard feature for Canon-mount lenses, is now employed in Nikon-mount lenses. More precise diaphragm and aperture control is possible because the diaphragm blades are driven and controlled by a motor through electronic pulse signals.
The lens also features moisture-resistant construction, and the Zoom Lock mechanism prevents undesired movement of the lens barrel under its own weight when the camera is angled downward while walking.
The device is compatible with the TAP-in Console, an optional accessory product. This provides a USB connection to a personal computer, enabling the user to easily update the lens’s firmware as well as to customize features, including fine adjustments to the AF and VC.
The lens is 123.9 mm / 121.4 mm long (Canon/Nikon) and weighs 710 g / 705 g (Canon/Nikon).
Tamron says its 18-400 mm f/3.5-6.3 Di II VC HLD lens in Canon and Nikon mounts will be available in late July.