Datasheet

FLD (“F” Low Dispersion) glass,
which has the highly desirable
anomalous dispersion characteristics
of fluorite. Careful arrangement
of these exclusive low-dispersion
glass elements gives Sigma lenses
superlative image rendition
untarnished by residual chromatic
aberration.
Sigma’s aspherical lens technology
contributes to outstanding
optical performance and compact
dimensions. These aspherical lens
elements compensate for the
spherical aberration and distortion
which cannot be completely
eliminated using conventional
spherical lens elements alone.
They are also key to reducing
the size and weight of high-power
zooms and other large lenses while
improving image quality. Sigma
has two kinds of aspherical lens
technologies. Hybrid aspherical
lens elements are made by forming
a polymer in an aspherical shape
on a glass lens surface. Glass mold
aspherical lens elements are made
by direct forming of the glass lens
material.
Sigma’s own Super Multi-Layer
Coating suppresses flare and
ghosting by preventing reflections
within the lens. All DG and DC
lenses in the current Sigma range
feature this original technology.
In digital cameras, flare and
ghosting may also be caused by
reflections between the image
sensor and lens surfaces. Here too,
Sigma’s Super Multi-Layer Coating
is highly eective, assuring images
of outstanding contrast.
SIGMA LENS TECHNOLOGY
The degree to which light is refracted
(bent) by glass depends on the
light’s wavelength (color). This fact
causes dierent colors of light to
focus at slightly dierent points.
The result is chromatic aberration,
the color fringing that is particularly
noticeable in telephoto lenses. Most
chromatic aberration can be removed
by combining a high-refractivity
convex lens element with a low-
refractivity concave element. But
residual chromatic aberration known
as “secondary spectrum” can only
be corrected with selected low-
dispersion glass materials.
In addition to ELD (Extraordinary Low
Dispersion) glass and SLD (Special
Low Dispersion) glass, Sigma uses
SLD, ELD or FLD glass element
Ordinary glass
Small secondary spectrum
Large secondary spectrum
Chromatic Aberration Correction
Exclusive low-dispersion glass
Original technology minimizes
secondary spectrum
Aspherical Lens
Eective correction of spherical
aberration and distortion
Sigma lens development is
dedicated to one thing: creating
great photographs. The key is
core technology research, which
lets us refine our advanced
processing and fabrication
technology, while finding
unconventional solutions to
optics challenges.
It is only when a lens can
deliver an excellent image
that you may appreciate
features of mechanical design
or control technology that
support operational comfort
and convenience. Technology
should be dedicated to ever
more faithfully capturing
precious moments and beautiful
scenes, with functionality
commensurate with this ability.
The scrupulous care with which
we approach all facets of
technology is reflected in the
extraordinary quality of each
and every Sigma lens.
Each of Sigma’s more than
40 lenses incorporates
original Sigma technology and
expertise gained from decades
of experience, guided by an
uncompromising philosophy.
Here we introduce Sigma's
technology, developed and
perfected to meet the varied
and sophisticated needs of
photographers while stimulating
fresh photographic creativity.
Each of Sigma’s more than
40 lenses incorporates original Sigma technology
and expertise gained from decades of experience,
guided by an uncompromising philosophy.
Super Multi-Layer Coating
Proprietary multi-layer coating
technology to virtually eliminate
ghosting and flare
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