Specification Sheet

With eBANDWithout eBAND
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Hybrid aspheric elements for spectacular build quality
and a compact design
ASL
Tamron lenses with the designation “aspherical” contain
several aspheric hybrid lens elements. These are designed to all
but completely remove imaging faults such as spherical aberrations
in Tamron high-performance zoom lenses. A hybrid aspherical
element can replace several other optical elements, contributing
to a compact form factor and equally high build quality with all
focal lengths and apertures. These innovative optics produce the
best possible image quality in a compact form, all while retaining
astonishingly large zoom ranges.
EXPAND YOUR
PHOTOGRAPHIC HORIZONS
eBAND Anti-Reex Coating
eBAND
The nano-compensation process developed by Tamron
allows a wafer-thin coating (1nm = 1/1,000,000mm) to be applied
to the surface of the lens. The nano-structure has an ultra-low
refractive index and ensures excellent anti-reex properties in
combination with the multi-layer compensation underneath. This
effectively minimises undesired mirroring and ghost images.
BBAR - the key to rst-class image quality
The innovative BBAR (Broad Band Anti-Reection) multi-layer
compensation from Tamron ensures that light that hits the surface
of the lens is not reected or dispersed. This means that loss of
light and contrast are avoided and ghost images are prevented.
BBAR multi-layer compensation also ensures the best possible
colour balance, which results in natural and precise colour
reproduction.
LD (Low Dispersion) Lens Element
LD
LD elements reduce chromatic aberrations such as colour
fringes on the contrast edges and reduced image sharpness. The
cause of these optical image faults is light of different wavelengths
being broken at different points. Telephoto and wide-angle focal
lengths are most affected by this. LD glass has a low colour
dispersion index, which causes sharper imaging. The lens element
effectively minimises unwanted colour fringes.
Camera compatibility
The designation Di (Digitally Integrated) refers to a lens developed
specially for the exacting requirements of digital cameras. Please
ensure when purchasing that the lens has the correct mount for
your camera system.
Di
For all DSLR cameras with full-format and APS-C sensors
Di II
For DSLR cameras with APS-C sensors
Di III
For mirrorless system cameras
Some models cannot be used with all mounts. You can nd an overview on pages 34-35.
Di lenses with built-in motors for Nikon and Di II lenses have no aperture ring.
TECHNOLOGY
Schematic diagram of the chromatic aberration with a normal
optical glass (left) and an LD glass (right)
Normal
optical
glass
LD glass Image planeImage plane
Tamron’s eBAND compensation effectively prevents mirror images that
can occur in back lit photographs as a result of reections on the lens
surfaces inside the lens.
Working mechanism of Tamron's eBAND compensation (right) compared
with a standard coating (schematic diagram).
Comparison of the partial dispersion factors with a normal
optical glass (left) and an AD glass (schematic diagram)
XLD (eXtra Low Dispersion) glass
XLD
XLD elements are made from high-performance optical
glass with an extremely low colour dispersion index. Its refractive
properties are similar to those in high-grade uorite. This effectively
prevents problematic chromatic aberrations. This means maximum
image sharpness will be achieved, even at the edges of the photo.
Legend - Lens construction (see lens designs in this brochure)
Hybrid aspheric lens LD element XLD element AD element XR element UXR element Aspheric ultra-precision moulded glass
Relatively even partial dispersion ratio.
Extremely high partial dispersion ratio relative
to a specic range of wavelengths.
AD glass
Normal optical glass
Super Performance -
For discerning photographers
SP
Tamron’s SP Series (Super Performance) meets the
highest standards in photography. The lenses are built to
precise specications to meet the demands of professional
photographers, with emphasis on the highest possible build
quality. Tamron doesn’t compromise in quality or cost - we
shoot for superior performance in every respect. The result
is a range of lenses marked by impressive, innovative
product design. Those looking for stellar performance need
look no further than Tamron’s SP lenses.
XR and UXR special glass for higher performance and
more compact lens construction
XR UXR
XR (eXtra Refractive Index) and UXR elements (Ultra
eXtra Refractive Index) are optical glasses with a particularly high
refractive index. Their properties allow a shorter overall length and
therefore lighter lenses with smaller diameters, without changing
the aperture size.
AD (Anomalous Dispersion) elements
AD
Optical lenses with an abnormal level of dispersion make a
signicant contribution to reducing colour fringes (chromatic aberra-
tions) at high light frequencies and improve overall imaging perfor-
mance. The combination of AD glass elements with other lenses
made from normal optical glass makes it possible to control light
dispersion at specic wavelengths. Axial and lateral aberrations,
which can be a particular problem when using telephoto lenses or
wide-angle lenses, can be signicantly reduced in this way.
Compensation for distortionCompensation for spherical aberrations
aspherical surface
Light's refractive
qualities mean that
incident light rays that
are not corrected can
cause distortions.
Tamron’s aspherical
construction principle
continuously balances
these light rays’ angle of
refraction.
spherical surface
corrected light rays on
the sensor level
uncorrected light rays on
the sensor level
Image planeImage plane
Image planespherical (normal) lens
aspherical lens
Compensation effect in a lens with an aspherical element (schematic
diagram)
TECHNOLOGY
Multi-layer coating
Multi-layer
coating
Nano-structured layer
Incident light Incident light
Reected light Reected light
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