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Sigma AF 150mm f/2.8 APO EX HSM macro DG D - Review / Test Report |
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Lens Reviews -
Nikon / Nikkor (APS-C)
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Page 1 of 3
Review by Klaus Schroiff, published February 2007
Lens kindly provided for testing purposes by Julio M. Alperi Gonzalez!
Introduction
The Sigma AF 150mm f/2.8 EX DG HSM APO macro is one of 5(!) dedicated
macro lenses by Sigma. Its focal length is quite unusual sitting in
between the mainstream 90/105mm f/2.8 and 180/200mm f/3.5 or f/4 variants
so it seems to be an attempt to combine the best of both worlds - a fast
f/2.8 max. aperture and a long reach.
It is a designated DG ("Digital Grade") lens featuring a new coating
optimized to (shiny) reflection characteristics of today's image sensors.
Unlike Sigma´s DC lenses it still covers the full 35mm image format
so it can also be used on a film SLR but in the scope of this report the lens
was tested using a Nikon D200 (1.5x crop factor) where its field-of-view
is equivalent to 225mm on a classic full frame camera. At the
time of this review the Sigma is available in Nikon (D), Canon, Sigma and
Four-Thirds mount.
The build quality of the lens is excellent - the outer barrel seems to be
made of metal covered with the typical EX ("Excellence") finish (crinkle style).
The broad, rubberized focus ring operates very smooth. The lens does not
extend during focusing nor does the front element rotate.
Regarding its relatively heavy weight Sigma was smart enough to provide a
dedicated tripod mount (detachable).
For a macro lens the speed of the near-silent HSM ("Hypersonic Motor") AF drive
is very decent but naturally a bit little compromised due to the very long focus path - it
simply takes some time to AF between the extreme ends of the focus range. In order to
prevent long range hunting in standard situations Sigma has implemented a focus limiter
where you can choose between full-range, 0.52m-infinity and 0.38-0.52m.
This set makes sense because the focus path from 0.38-0.52m is about as long as
between 0.52m-infinity. Thanks to the HSM AF drive manual focusing is always possible in
single-shot AF mode.
Regarding its IF (internal focusing) design the Sigma should loose about 1.5 f-stops at
its most extreme macro setting but unlike the Micro-Nikkors the effective max. aperture
is not adjusted (update: the latest generation does). The min. working distance of the lens (@ 0.38m focus) is 20cm
(front-element to object).
| Specifications |
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| Equiv. focal length | 225 mm (full format equivalent) |
| Equiv. aperture | f/4.2 (full format equivalent, in terms of depth-of-field) |
| Optical construction | 16 elements in 12 groups inc. 2x SLD elements |
| Number of aperture blades | 9 |
| min. focus distance | 0.38 m (max. magnification ratio 1:1) |
| Dimensions | 137 x 80 mm |
| Weight | 895 g |
| Filter size | 72 mm (non-rotating) |
| Hood | barrel-shaped (included), snap-on type |
| Other features | Floating system. Tripod-mount. |
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