Format: APS-C (crop)
Type: Zoom lens
Focusing: Auto Focus (AF)
Lens mounts: Canon EF, EF-S, Sony A / Minolta A, Nikon F (FX, DX), Pentax K, Sigma SA
First year of production: 2008
Optical design: 16 elements in 12 groups (3 AS, 1 SLD)
Features: Ultra-Sonic Motor, Optical stabilisation | |
Additional information:
The Sigma 18-125 mm f/ 3.8-5.6 DC OS HSM pros
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Diagonal angle of view 69.3°- 11.4° (1.7х)
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Equivalent focal length 28-200 mm (1.6х)
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Max. magnification 1:3.8
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Minimum aperture 22 - 32
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Diameter 74 mm
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Max. focal length 14 cm
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Weight 490 -505 g
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LH780-04 hood is completed with the lens.
The Sigma 18-125mm F3.8-5.6 DC OS HSM is a compact all-purpose 7x zoom ratio lens equipped with an optical stabilizer and an HSM autofocus drive (autofocus for the Nikon bayonet mount only). The lens is designed for small-format DSLR only and cannot be used on full format and film cameras. Its optical scheme includes three aspherical lenses (two hybrid and one molded) and one SLD lens. The super multi-coating reduces flare and halation, and corrects color rendering.
Internal focusing eliminates the front element rotation, which enables the use of a polarized filter and a petal hood. The Sigma 18-125 mm f/ 3.8-5.6 DC OS HSM is equipped with a zoom lock mechanism which prevents barrel extension under its weight when the lens is directed downwards. The lens has a single mode Optical Stabilizer switch, but this single mode is able to detect panning . There is a strange feature of the OS - the image in the viewfinder jerks upwards when the camera is switched on even if the OS is off. The distance scale is marked on the lens barrel.
The Sony and Pentax bayonet mounts are not equipped with the OS, and consequently have no OS index, because the bodies of these digital cameras have a built-in Anti-shake function. A camera for the Pentax bayonet mount must support an HSM, otherwise the autofocus does not function. The G type lens for the Nikon bayonet mount has no aperture ring, and the autofocus functions on all cameras.
The Sigma 18-125 mm f/ 3.8-5.6 DC OS HSM pros
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solid build for this class,
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very good image quality in the frame center at all focal lengths,
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good image quality on the edges at the focal range of 18-70 mm,
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low distortion for this class,
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low vignetting as compared with competing lenses,
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reasonably corrected coma,
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rather good functioning in bright light,
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quiet, fast and precise autofocus on the Nikon bayonet mount ,
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effective image stabilization.
The Sigma 18-125mm F3.8-5.6 DC OS HSM cons
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worse image quality on the edges at maximum focal length,
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considerable wide-angle distortion,
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no HSM for the Canon bayonet mount,
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no FTM for the Canon bayonet mount
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real 2-3 f/ stops for the OS instead of 4 claimed by Sigma.
Links to online resources:
PDF Files:
Posted by: dv Date of publication: 31.10.2010
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