Tamron SP 24-70MM F/2.8 DI VC USD
Tamron announced the official release of their SP 24-70MM F/2.8 DI VC USD lens today. They had previously said that the lens was in development, but now it's in production. The release date for the Canon mount version is April 26th 2012 with the Nikon mount version following soon after. No date has been set for release of the lens in the Sony mount. Note that the Sony version will not be optically stabilized because Sony use an in-camera sensor shift stabilization scheme. The price of the Tamron SP 24-70MM F/2.8 DI VC USD in a Canon EOS mount $1299. This compares with current prices of around $1399 for the original Canon EF 24-70/2.8L USM and $2299 for the new EF 24-70/2.8L II USM, neither of which are optically stabilized.
My opinion is that the addition of optical stabilization is a big plus, and I can't really understand why Canon didn't include IS in their MkII version of the EF 24-70/2.8L. Perhaps it was a matter of cost. With the unstabilized EF 24-70/2.8L II USM selling for $2299, maybe Canon thought that the price with IS added would simply be too high for the market to bear. Luckily Tamron's price of $1299 is quite reasonable, and in fact cheaper than the original unstabilized MkI version of the Canon EF 24-70/2.8L (which can still be found new).
Tamron's MTF data for the Tamron SP 24-70MM F/2.8 DI VC USD
At the moment it's not possible to compare images taken with the Canon lenses with those taken with the new Tamron because neither the new Canon EF 28-70/2.8L II USM nor the Tamron SP 24-70MM F/2.8 DI VC USD are yet available. However I've been quite impressed with the optical quality of Tamron's recent releases (as well as their VC stabilization system), so I have high hopes that the SP 24-70MM F/2.8 DI VC USD will perform well. As soon as it becomes available in the US I will be testing one. My request is already in! The published MTF data indicates that the new Tamron 24-70/2.8 VC USD should be sharper then the current Canon EF 24-70/2.8L USM but not quite as sharp as the new Canon EF 24-70/2.8L II USM. However I usually take published MTF data with a grain of salt. It's not a 100% reliable predictor of lens performance. Many published curves are theoretical rather than measured on a production lens. Still, it is a positive sign that points to potentially very good performance from the Tamron SP 24-70MM F/2.8 DI VC USD.
Optical construction of the Tamron SP 24-70MM F/2.8 DI VC USD
The optical design sounds good, with three LD (low dispersion) glass elements, three glass molded aspheric elements, one hybrid aspheric element and two XR (high refractive index) elements included in the 17 element/12 group construction. The lens also features a 9 blade rounded shape iris for smoother out of focus regions (better Bokeh). The SP 24-70MM F/2.8 DI VC USD is said to be "moisture resistant", so it has some degree of weather sealing. The ultrasonic motor (USD) has full time manual focus capability.
The Tamron SP 24-70MM F/2.8 DI VC USD is available for pre-order from Adorama. It will ship sometime after the 26th April release date but no charges are made until it actually ships.
The can also be pre-ordered right now from B&H. It will ship when in stock, which will be sometime after April 26th 2012. No charges are mode until the lens ships.
Tamron SP 24-70MM F/2.8 DI VC USD Specifications
| Model | A007 |
| Focal length | 24-70mm |
| Maximum aperture | F/2.8 |
| Minimum aperture | F/22 |
| No. of diaphragm blades | 9 (rounded diaphragm) |
| Angle of view(diagonal) | 84°04' - 34°21' (with full-size SLR cameras) 60°20' - 22°33' (with APS-C sized sensor digital SLR 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 | f82mm |
| Length | 108.5mm (4.3 in) |
| Diameter | f88.2mm (3.5 in) |
| Weight | 825g* (29.1 oz) |
| Standard accessories | Flower-shaped lens hood |
| Compatible mounts | Canon, Nikon, Sony |
Here's the Tamron Press Release:
The Tamron SP 24-70MM F/2.8 DI VC USD is available for pre-order from Adorama. It will ship sometime after the 26th April release date but no charges are made until it actually ships.
TAMRON ANNOUNCES WORLD'S FIRST [1] FULL-SIZE, HIGH SPEED STANDARD ZOOM WITH BUILT-IN IMAGE STABILIZATION - SP 24-70MM F/2.8 DI VC USD (MODEL A007)
New Super Performance full-frame zoom lens features class-leading resolution and Tamron's proprietary VC (Vibration Compensation)April 5, 2012, Commack, NY -Tamron USA, Inc. announced the SP 24-70mm F/2.8 Di VC USD (Model A007), the world's first1 full-size high-speed standard zoom lens equipped with VC (Vibration Compensation) image stabilization and USD (Ultrasonic Silent Drive)[2], with resolution at the top of its class, will be available starting April 26, 2012 in Canon mount with Nikon mount following. Delivery of the Sony mount version has not been released.
Product Features
World's first full-size, high-speed standard zoom with built-in VC (Vibration Compensation)[3]. 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. Uses specialized 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[4], the lens achieves gorgeous blur effects. Features USD (Ultrasonic Silent Drive) to power a speedy AF drive together with a continuous manual mechanism. This high-speed standard zoom lens has a wide-end focal length of 24mm that expands the photographic area. 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. Moisture-resistant construction helps prevent water from penetrating the lens.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 ceramic balls. The VC lens elements are held in place only by contact with the ceramic 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.