- Compact Fast Zoom with VC (Vibration Compensation)..
- Fast Constant F/2.8 Aperture..
- For use on APS-C size DSLR cameras..
- 11.4-Inch minimum focusing distance / 1: 4.8 Maximum magnification ratio..
- Internal Focusing..
From the Manufacturer
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A masterpiece of innovative optical design, this compact,
lightweight, high performance standard zoom (26-78mm equivalent)
delivers a fast F/2.8 aperture over its entire focal-length range
for maximum creative flexibility. To maintain critical sharpness
when shooting handheld it includes VC (Vibration Compensation),
Tamron’s state-of-the-art, tri-axial image stabilization system.
Three compound aspheric elements, special LD glass, and BBAR
coatings ensure superb correction, color fidelity, and freedom
from flare. A minimum focus distance of 0.29m (11.4 inches )
offers exciting close-up rtunities.
Compact & lightweight the AF 17-50mm is ideal for shooting
on-the-go SP AF17-50mm F/2.8 XR Di II VC Highlights
Di II
Lenses are designed for exclusive use on digital cameras with
smaller-size imagers and inherit all of the benefits of our Di
products. These lenses are not designed for conventional cameras
and digital cameras with image sensors larger than 24mm x 16mm.
Vibration Compensation (VC)
Handheld camera shake is the leading cause of blurry and unsharp
pictures. Several leading companies now make lenses with built-in
optical image-stabilization systems that sense the amplitude and
direction of the shake and compensate by moving optical groups
within the lens. Tamron’s exclusive new Vibration Compensation
(VC) system that’s built into the Tamron AF28-300mm F/3.5-6.3 XR
Di VC LD Aspherical (IF) Macro and the Tamron AF18-270mm
F/3.5-6.3 Di-II VC LD Aspherical (IF) Macro lenses performs a
similar function, but it executes it much more effectively due to
its innovative breakthrough design
* VC delivers blur free - handheld images for incredible results
* VC mechanism employs a three-coil system
* Lens element compensates for vibration using 3-steel balls
(making movement quiet & smooth)
* Exceptional images at slower shutter speeds – reduces the need
for a tripod
* Bring out contrast to motion & stillness
* Eliminate the need to shoot with a Flash
VC Off - VC On
Aspherical Elements (ASL) Provide the Ultimate in Image Quality
and Compactness)
Tamron uses several hybrid aspherical lens elements in many
lenses bearing the Aspherical designation. These innovative
optics allow us to achieve the ultimate in image quality, and at
the same time produce lenses that offer remarkable zoom ranges in
extraordinarily compact packages. By perfecting theses
cutting-edge advances for series production, Tamron has advanced
the state of optical design, and virtually eliminated spherical
aberration and image distortion from the high-power-zoom
series.Through the effective application of Hybrid Aspherical
Technology, one lens elemen tcan take the place of multiple
elements without compromising performance. This is what allows us
to produce remarkably compact long-range lenses that deliver a
uniformly high level of image quality at all focal lengths and
apertures.
Achieve the ultimate in image quality with Asperical (ASL)
lenses Extra Refractive Index Glass (XR)
Extra Refractive Index (XR) glass can bend light rays at steeper
angles, thereby decreasing the physical length of the lens while
enhancing imaging performance by minimizing optical aberrations.
This has allowed Tamron to develop a line of shorter,
smaller-diameter, lighter lenses without sacrificing lens speed,
and actually upgrading image quality compared to older designs.
XR glass is costlier than conventional glass but it yields
enhanced optical power distribution, making possible many of the
outstanding and innovative lens designs that bear the XR
designation. XR glass, with its superior light-bending power,
makes it possible to design a short-barrel lens with the same
light-gathering ability (aperture value) as a long-barrel
lens—even with a smaller lens diameter. By using this principle
Tamron has been able to shorten the length of the entire optical
system and produce lighter, more compact lenses of the same
speed, and also to provide greater zoom ranges in lenses that are
much more convenient to carry by hand.
Special glass for better performance and more compact lens
designs Super Performance (SP) for Discriminating Shooters
Tamron SP (Super Performance) series is a line of
ultra-high-performance lenses designed and manufactured to the
exacting specifications demanded by professionals and others who
require the highest possible image quality. In creating SP lenses
Tamron’s optical designers put their foremost priority on
achieving superior performance parameters—they are all designed
to a higher standard with little regard for cost constraints. As
a result, Tamron lenses bearing the SP designation feature
impressive and innovative designs that have established an
enviable reputation for excellence among those knowledgeable
photographers that demand the very best.
Low Dispersion (LD)
Low dispersion (LD) glass elements in a lens help reduce
chromatic aberration; the tendency of light of different colors
to come to different points of focus at the image plane.
Chromatic aberration reduces the sharpness of an image, but glass
with an extremely lowdispersion index, has less of a tendency to
separate (defract) a ray of light into a rainbow of colors. This
characteristic allows the lens designer to effectively compensate
for chromatic aberration at the center of the field (on axis), a
particular problem at long focal lengths (the telephoto end of
the zoom range), and for lateral chromatic aberration (towards
the edges of the field) that often occurs at short focal lengths
(the wide-angle end of the zoom range.)
Low Dispersion (LD) Glass for Greater Lens Sharpness
Internal Focus (IF)
Internal focusing (IF) provides numerous practical benefits to
photographers including a non-rotating front filter ring that
facilitates the positioning of polarizing and graduated filters,
and more predictable handling because the lens length does not
change during focusing. Even more important, Tamron’s Internal
Focusing (IF) system provides a much closer minimum focusing
distance (MFD) throughout its entire focusing range. In addition,
IF improves optical performance by minimizing illumination loss
at the corners of the image field, and helps to suppress other
aberrations that become more troublesome at different focusing
positions
Zoom Lock (ZL)
Another original Tamron mechanical engineering concept is the
Zoom Lock (ZL), a simple convenience feature that prevents
undesired extension of the lens barrel when carrying the
camera/lens unit on a neck strap..