Sigma APO 50-150mm F/28 EX DC OS HSM Lens Review
80 % Rs.73,500
Lenses in the (equivalent) focal range of approximately 70-250 mm are considered very useful for day-to-day photography – be it portraits, table-tops, or general outdoor shooting. Combine that with a reasonably fast aperture ( like f/2.8), and you get an efficient workhorse. That’s exactly what Sigma’s APO 50-150 mm f/2.8 EX DC OS HSM lens is. Incidentally, this is the second 50-150mm f/2.8 lens from Sigma; the earlier version had no optical stabiliser. Let’s see how the new lens fares on our test-bench.
Design and Build Quality
Designed for APS-C size sensor cameras, the Sigma APO 50-150 mm f/2.8 EX DC OS HSM lens is beautifully crafted in matte black and looks very elegant. The outer body is made from engineering plastic and metal and feels adequately strong. A removable tripod mounting collar with a large, comfortable knurled knob is provided. The lens mount is made from metal. Filter diameter is 77 mm. The lens is available in Canon, Nikon and Sigma mounts.
Key Features
The Sigma APO 50-150 mm f/2.8 EX DC OS HSM lens we reviewed had a Nikon mount and was tested using a Nikon D80 body. On compatible Nikon bodies, the equivalent focal length is 75-225 mm (would be equivalent to 80240 mm on compatible Canon bodies). The angle of view is 27.9-9.5 degrees. The lens is constructed with 21 elements in 15 groups (includes 6 SLD – Super Low Dispersion – glass elements to counter possible chromatic aberrations). It is compact in size (about 7.8 inches without the supplied lens hood) and weighs approximately 1410 g ( Nikon mount, including the lens hood but without the front/rear lens caps). The zoom ring is nice and broad (40 mm), clearly marked at 50, 70, 100 and 150 mm settings and the focussing ring is well-damped. A distance scale, legibly marked in feet and meters is placed under a plastic window behind the focussing ring. Super multi-layer coating helps to reduce flare and ghosting and ensures sharp images with good contrast even with the lens wide open. The lens incorporates an inner focussing / inner zooming system (maintains the same length during focussing and zooming), whilst the Hyper Sonic Motor ( HSM) ensures fast and quiet auofocussing. A Focus Mode Switch (AF-M) allows you to choose between autofocus and manual focus and full-time manual focus override is possible during autofocussing. The Sigma APO 50-150mm f/2.8 EX DC OS HSM lens incorporates a 2-mode Optical Stabiliser (OS) which helps to reduce hand-shake by up to 4 stops. Mode 1 is for general work, while Mode 2 detects vertical movements. At its minimum focussing distance of 80 cm /31.5 inches (at 150mm setting), the lens offers a magnification of 1:6.4.
Its rounded 9-bladed diaphragm provides a nice ‘ bokeh’ of out-offocus background elements. Sigma’s 1.4x and 2x DG-series teleconverters can be used to extend the zoom range to 70-210 mm f/4 and 100-300 mm f/5.6 respectively (Sigma, in the accompanying leaflet, clearly mentions not to use teleconverters from other manufacturers).
Ergonomics
The Sigma APO 50-150 mm f/2.8 EX DC OS HSM lens was easy to handle and balanced perfectly well on our Nikon D80 body. The tripod collar is placed at the perfect point of balance but was a bit ‘sticky’ on our review piece (rotating the camera/lens combo from horizontal to vertical was a bit jerky). The location of the AF-M switch and the OS ‘on/off’ switch is very convenient, allowing you to operate the switches using the left hand thumb. Since the front element does not rotate during focussing and zooming, using polarizing filters and graduated neutral density filters is convenient.
Performance
The zoom ring as well as the focus ring was well damped. Autofocus was quick even with our ageing D80 body. The lens produced good sharpness throughout the zoom range though edge sharpness felt a tad less sharp, especially at f/2.8. This is quite normal, especially for a ‘fast’ zoom lens. The images could be further sharpened effectively in Photoshop. Barrel distortion at 50mm (effectively 75mm) was easily noticeable, which reduced to a minimal as the focal length changed towards the longer end. Corner darkening with the lens wide open (at
f/2.8) was also noticed, which reduced quite a bit by f/4, and was negligible by f/5.6. Most users may not notice the slight darkening this lens produced at f/5.6. Normal amount of flare could be noticed in strong against-the-light shots and magenta fringing was noticed when the against-the-light shots were enlarged to 200%. We would rate the overall performance as very good.
Value for Money
The Sigma APO 50-150 mm f/2.8 EX DC OS HSM lens is available at an MRP of Rs.73,500. At this price, we consider the lens rather expensive.
SPECIFICATIONS
Lens construction : 21 elements in 15 groups ( includes 6 SLD glass elements) Coatings : Super Multi-layer coatings Focussing : Internal Angle of view : 27.9-9.5 degrees Diaphragm blades :9 Aperture range : F/ 2.8- 22 Min. Focussing distance : 80 cm ( 31.5 inches) Filter size : 77 mm dia. Max. Magnification : 1: 6.4 Dimensions (D X L) : 86.4 x 197.6 mm
( 3.4 x 7.8 inches)