- Designed for use with full frame digital SLR cameras. May also be used with smaller APS-c size sensors with a corresponding effective increase in focal length to about 150mm with most cameras.
- Focuses down to 1:1 magnification ratio at its closest working distance of 12.3 inches.
- A hood adapter, lens hood, front & rear lens caps are included with the lens.
- Filter size 62mm.
Product Description
-------------------
The Sigma 105mm f/2.8 EX DG OS HSM Macro Lens for Canon EOS DSLR
Cameras offers advanced performance of close-up photography. The
OS (Optical Stabilizer) system enables handheld close-up
photography. A Special Low Dispersion (SLD) lens and one high
refractive index SLD lens provide excellent correction for all
types of aberration and distortion. A floating focusing system
moves two different lens groups in the optical path to different
positions. This system compensates for astigmatic aberration and
spherical aberration and provides extremely high optical
performance from infinity to 1:1 Macro.The Super Multi-Layer
Coating reduces flare and ghosting, providing high contrast
images. It is also possible to use this lens with Sigma's APO
TELE CONVERTERS. The HSM (Hyper Sonic Motor) ensures quiet and
high speed autofocus as well as full-time manual focus
capability. This lens features a splash proof design for use in
harsh conditions and a rounded 9 blade diaphragm creating an
attractive blur to the out of focus areas of the image.
From the Manufacturer
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High performance, large aperture medium telephoto macro lens with
OS (Optical Stabilizer).
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High performance, large aperture medium telephoto macro lens with
OS (Optical Stabilizer). SLD glass provides good control of
aberration and the floating inner focus system ensures high
rendering throughout the focusing range. By using Sigma's APO
Tele Converter, it is possible to take photos at greater than 1:1
magnification. HSM ensures a quiet and high speed AF as well as
full-time manual focus override. This lens has a rounded 9 blades
diaphragm which creates an attractive blur to the out of focus
areas.
Large aperture medium telephoto macro lens
------------------------------------------
This medium telephoto macro lens allows you to maintain an
appropriate distance from subjects while still getting close up
photos. Since the working distance at its closest focusing
position is 142mm, shadows of the lens and camera will not affect
photography making it suitable for taking photos of subjects,
such as flowers, under natural lighting conditions. In comparison
to the Sigma 50mm and 70mm macro lenses, the main subjects can be
defined with perfectly smooth and blurred backgrounds.
No Super Multi-Layer Coating (left). With Super Multi-Layer
Coating (right).
High rendering performance
--------------------------
The lens power layout produces excellent optical performance.
High refractive index SLD (Special Low Dispersion) glass corrects
chromatic aberration, spherical aberration and field curvature.
It ensures high rendering performance at all shooting distances.
The Super Multi-Layer Coating reduces flare and ghosting,
maintaining quality images with high contrast.
No Optical Stabilizer (top). With Optical Stabilizer (bottom).
Handheld photography with ease
------------------------------
Sigma's OS (Optical Stabilizer) system offers effective
correction of approximately 4 stops. As the stabilization effect
is visible through the viewfinder, it aids composition and
accurate focusing.
* The OS effectiveness will gradually decrease as the shooting
distance becomes shorter.
Floating inner focusing
-----------------------
This lens incorporates floating inner focusing which moves two
lens groups separately. This minimizes aberrations which occur as
shooting distance changes, and enables stable rendering of the
image from infinity to 1:1 magnification. This also corrects
image distortion, especially when taking close-up pictures. Since
focusing does not change its overall length, this lens is easy to
hold and use.
Hyper Sonic Motor
Quiet and speedy AF
-------------------
HSM indicates lenses equipped with a Hyper Sonic Motor, driven by
ultrasonic waves. HSM provides quiet and high speed AF. It is
also possible to use full-time manual focus, even if the lens is
set to autofocus.
Rounded 9 blades diaphragm
--------------------------
This lens has a rounded 9 blade diaphragm which creates an
attractive blur to the out of focus areas. This also creates
smooth, rounded out of focus highlights when taking photos which
have a strong light source in the background such as lights
shining on the surface of water.
Lens Construction
-----------------
In a conventional lens, focusing requires an extension of the
entire lens or the front lens group. However, to better
accommodate autofocusing mechanisms and closeup photography, a
need has arisen for lenses that do not change their length during
focusing or suffer from focus-dependent variation in aberration.
Therefore, Sigma has developed focusing systems that only move
elements within the lens barrel. These incorporate smaller and
lighter moving lens elements which help improve auto-focus speed.
With their unchanging barrel length and small variation in the
center of gravity, these lenses also enhance balance and
stability for the photographer. Furthermore, since the front of
the lens does not rotate, polarizing filters can be used with
extra convenience.
Specifications
--------------
Lens Construction 16 Elements in 11 Groups Angle of View 23.3
degrees Number of Diaphragm Blades 9 Blades (Rounded diaphragm)
Minimum Aperture F22 Minimum Focusing Distance 31.2cm / 12.3in.
Maximum Magnification 1:1 Filter Size Diameter 62mm Dimensions
Diameter 78.3mm x Length 126.4mm / 3.1in. x 5.0in. Weight 725g /
25.6oz.
MTF Chart
---------
MTF (Modular Transfer Function) is one of the measurements that
evaluates a lens' performance, and it contrasts sensitivity at
different spacial frequencies. The horizontal axis is in
millimeters and shows the distance from the center of the image
toward the edges, and contrast value (highest value is 1) is
shown in the vertical axis.
The readings at 10 lines per millimeter measure the lens'
contrast ability (red lines), repeating fine parallel lines
spaced at 30 lines per millimeter measure the lens' sharpness
ability (green lines), when the aperture is wide open. Fine
repeating line sets are created parallel to a diagonal line
running from corner to corner of the frame, are called Sagittal
lines (S) and sets of repeating lines vertical to these lines are
drawn, called Meridional (M) line sets.
Distortion
----------
effective distortion: When you take a picture of a lattice
pattern, it will appear as the blue dotted line shows. the red
line illustrates how the lattice pattern will appear in the
actual picture when any lens distortion is taken into account.
relative distortion: In this chart, the horizontal axis shows the
ideal image height (the distance from the center to the edge of
the image [mm]). The vertical axis shows the extent of
distortion. The extent of the distortion is represented by how
much Y, which is the actual image height, grows (or shrinks)
against Y0 which is the ideal image height.
Extent of distortion: D[%]=(Y-Y0/Y0)x100
When you take the picture of a square object, if the distortion
a show a minus value, the image will be seen as expanded
(Barrel distortion). If the distortion a is a plus value, it
will be seen as a recessed (pincushi on distortion). When the
distortion value is close to 0, the appearance of distortion is
very minimal.
Vignetting
----------
The horizontal axis shows the image height (the distance from the
center to the edge of the image [mm]). The vertical axis shows
the a of light in the image (based on the a of light in
the image center being 100%). If the peripheral a of light
is lower than the center, the four corners of the image will be
darker (vignetting).