Sigma AF 150mm f/2.8 APO EX HSM macro DG D - Review / Test Report
Lens Reviews - Nikon / Nikkor (APS-C)

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
Equiv. focal length225 mm (full format equivalent)
Equiv. aperturef/4.2 (full format equivalent, in terms of depth-of-field)
Optical construction16 elements in 12 groups inc. 2x SLD elements
Number of aperture blades9
min. focus distance0.38 m (max. magnification ratio 1:1)
Dimensions137 x 80 mm
Weight895 g
Filter size72 mm (non-rotating)
Hoodbarrel-shaped (included), snap-on type
Other featuresFloating system. Tripod-mount.




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