February 6, 2012
Tamron unveils new full frame f/2.8 lightweight zoom
Tamron has announced a new standard zoom lens designed for full frame DSLR's combining high speed in a lighweight bundle (plus vibration reduction).
Tamron's Press Release did not include a price or details on when it will be available but it did include some interesting specs:
February 6th, 2012, Saitama, Japan － Tamron Co., Ltd., a leading manufacturer of optical equipment, announced the development of the SP 24-70mm F/2.8 Di VC USD (Model A007), a full-size high-speed standard zoom lens equipped with VC ( Vibration Compensation) image stabilization and USD ( Ultrasonic Silent Drive), with resolution at the top of its class.
The price and availability of the SP 24-70mm will be announced at a later date.
1. A full-size, high-speed standard zoom with built-in VC ( Vibration Compensation). Even when shooting in low-light conditions with a slow shutter speed to render sharpness, Tamron’s acclaimed VC allows for stable handheld camera work, to more fully enjoy the benefits of this high-speed zoom lens.
2. Uses special high-grade glass in the three LD elements, three glass molded aspherical lenses, one hybrid aspherical lens and two XR (Extra Refractive Index) glasses, delivering top-of-the-class quality images suited to this high-grade lens. Using a rounded diaphragm, the lens achieves gorgeous blur effects. This rounded diaphragm retains a nearly circular shape even when taken two stops down from its fully open state.
3. Features Tamron proprietary USD ( Ultrasonic Silent Drive) to power a speedy AF drive together with a continuous manual mechanism.
4. This high-speed standard zoom lens has a wide-end focal length of 24mm that expands the photographic area.
5. The lens adopts the new technology including the latest optical design, VC ( Vibration Compensation) image stabilization and USD ( Ultrasonic Silent Drive), all in a lighter and more compact package.
6. Moisture-resistant construction helps prevent water from penetrating the lens.
• Model: A007
• Focal length: 24-70mm
• Maximum aperture: F/2.8
• Angle of view (diagonal): 84°04’ －34°21’ (for full frame 35mm format cameras)
• 60°20’ －22°33’ (for APS-C format cameras)
• Lens construction: 17 elements in 12 groups
• Minimum focus distance: 0.38m (15.0 in)
• Maximum magnification ratio: 1:5 (at f=70mm: MFD 0.38m)
• Filter size: φ82mm
• Length: 108.5mm*
• Entire Length: 116.9mm*
• Diameter: φ88.2mm
• Weight: 825g*
• No. of diaphragm blades: 9 (rounded diaphragm)
• Minimum aperture: F/22
• Standard accessories: Flower-shaped lens hood
• Compatible mounts: Canon, Nikon, Sony
* Length, entire length and weight values given are for the Nikon mount.
* Entire length is the distance between the tip of the lens and the tip of the protrusion.
* The Sony mount does not include VC, because the body of Sony digital SLR cameras includes image stabilization functionality. The product name for Sony cameras is “SP 24-70mm F/2.8 Di USD” without the VC designation.
VC ( Vibration Compensation)
VC ( Vibration Compensation) is Tamron’s proprietary image stabilization system. Tamron’s VC is a three-coil system, whereby three driving coils activate the shake-compensating VC lens group electromagnetically via three steel balls. The VC lens elements are held in place only by contact with the steel balls, achieving smooth movement with little friction. This provides a stable viewfinder image with excellent tracking performance. And as the VC lens may be moved in parallel using only the motorized control, the mechanical structure has been simplified, enabling the creation of a more compact lens.
New VC system (moving coil method)
Tamron’s original VC image stabilization mechanism utilized a moving magnet system whereby a heavy magnet was positioned near the moving VC lens element. In the new VC unit the positions of the magnet and the coil are reversed, because of this the VC optical lens element is attached to the coil. The new VC mechanism employs a moving coil mechanism with a lightweight coil, and the lighter coil reduces the load on the drive system. Thus, the lighter, more compact new VC unit contributes to the lens’s overall light weight and compact size.
Because the 24-70 mm F/2.8 Di VC USD is a high-speed zoom lens with maximum aperture of F/2.8, its VC system must drive a lens that is larger and heavier than other zooms. Therefore, the shape, size and layout of the drive coils are all designed to obtain sufficient thrust. The result is a full-size, high-speed zoom that provides the same high level of compensation effect.
About the ultrasonic motor
In the ultrasonic motor, a piezoelectric element arranged in a ring formation generates ultrasonic vibrations in a metallic ring stator, and the vibration energy is used to rotate a metallic ring rotor that is attached to the stator. The rotation energy is in turn transferred from the metallic ring rotor to operate the focus lens.
Posted by flashdeadline at February 6, 2012 3:16 PM