Additional information:
The Sigma APO Macro 180 mm f/ 2.8 EX DG OS HSM
-
Diagonal angle of view 13.7 ° (SD1 - 9.0 °)
-
Max. magnification 1:1
-
Internal floating focusing (IF)
-
Diameter 95 mm
-
Compatibility with 1.4x and 2х EX DG APO teleconverters
-
Price $ 2,400
The Sigma APO Macro 180mm f2.8 EX DG OS HSM is the fastest 180 mm macro lens on today's market- the rest have a maximum aperture of f/3.5; besides, it is the only lens with a focal length like that which has an optical stabilizer.
The optical scheme of the lens consists of 19 elements in 14 groups, including three FLD elements ( glass with a low refractive index and low dispersion as compared to ordinary optical glass and with a performance equal to fluorite glass, used to correct aberrations) The super multi coating reduces flare and halation and provides sharp and high contrast images even at a maximum aperture.
Equipped with its own optical stabilizer (even for Sony) the lens offers the use of shutter speeds approximately 4 stops slower than would otherwise be possible, enabling handheld close-up photography. The HSM (Hyper Sonic Motor) ensures quiet and high-speed autofocusing, as well as full time manual focusing (FTM). An additional Sigma teleconverter enables shooting with even greater working distance or with a magnification ratio larger than 1:1.
Short-distance photography may be problematic, especially while taking life-size pictures of timid animals and insects without scaring them away or close-up photos of little objects without shadowing them. A larger focal length of the Sigma 180mm f/2.8 EX DG OS HSM eliminates many of these problems, allowing you to step back from the object of shooting.
A larger focal length not only reduces optical distortion, that may be problematic for close-up photography, but may also isolate the lens from unwanted details of back- and foreground, especially using one's own closest points of focus at maximum aperture.
Besides caps, the Sigma APO Macro 180mm F2.8 EX DG OS HSMis completed with:
-
LH927-01 hood
-
HA927-01 adapter for a crop
-
TS-21 tripod socket
Vignetting (F2.8 F5.6 F11)
Distortion
Evaluation of Sigma designations:
-
AF for autofocus.
-
APO- an apochromatic lens, minimizing chromatic aberration. Lenses designated APO can be used with EX teleconverters.
-
HSM - a hyper sonic motor drive providing silent and fast focusing.
-
EX - a high-quality line of lenses, combining reliability, convenience and excellent optical characteristics.
-
IF - a mechanism of internal focusing does not affect the lens size while focusing and without the front element rotation.
-
DG - a full format lens optimized for DSRL cameras.
-
OS - optical stabilizer.
-
MACRO - macrography with the max. magnification ratio of 1:1.
Links to online resources:
PDF Files:
Posted by: dv Date of publication: 10.01.2012
| 
