Anno Huidekoper : June 14th 2009 - 17:30 CET
|Sigma macro lens review
Field test Sigma AF 150mm f/2.8 APO EX macro DG lens : During the annual photography course I offer in France, I made extensive use of the Sigma AF 150mm f/2.8 APO EX macro DG lens. There were a few things I wondered about: 'Is its optical quality high enough to serve a 20 million pixel full frame Canon 5D Mark 2?'. Secondly; since I also frequently work in a studio environment; 'Is the auto focus fast and accurate enough in a rather dark studio environment?'. And lastly; 'How does it feel working with a slightly deviating focal length of 150mm for nature and studio photography?'. |
Sigma macro lens assortment
Sigma provides no less than 5 different macro lenses which are all suitable for APS-C and full frame sensor format. The focal lengths are 50, 70, 105, 150 and 180mm. The brightness of the Sigma lenses is f/2.8 in all but one case. It's only the 180mm lens that provides a brightness of f/3.5. Considering the 35mm format, the focal lengths of 50, 70 and 105mm are very short for a macro lens. You will be so close to the subject that your features will cast a shadow on it. It's especially at focal lengths of 150 and 180mm that you're keeping at a distance from the subject.
Sigma macro lens review
If you have an APS-C camera with a 1.5x crop factor at your disposal, the focal lengths of 150 and 180mm are rather large for a macro lens due to the risk of blur caused by jitter. Since I work with a full frame body, the 150mm f/2.8 is more convenient than the 180mm f/3.5 version, or at least on paper. After all, the 150mm lens is shorter, lighter, brighter and even a lot cheaper! Not one Sigma macro lens features a stabilization system to prevent blur caused by jitter.
Sigma EX macro lens - Metal mount & Rubber coating
The matte black finish of this macro lens immediately reveals that it belongs to the more expensive Sigma EX range. The mount is made of metal and it all feels very solid. The rubber coating of the focus ring provides a comfortable grip, and fortunately a large lens hood featuring a bayonet mount is included. Also standard included is the rotatable tabletop tripod of which the table is just about large enough. If you want to get rid of some weight, this Sigma macro lens weighs almost half a kilo more than the Sigma 105mm f/2.8 macro, you can easily remove the table from the lens.
Sigma HSM auto focus
The Sigma features silent HSM auto focus. The auto focus is fast, but not as fast as for example the Canon L lenses. However; if you compare the speed to the Nikkor 180mm f/2.8, you will find the AF of the Sigma working a lot faster. In general circumstances, the Sigma 150mm f/2.8 only rarely hunts if used in combination with the Canon 5d Mark 2. Should this phenomenon occur, you can opt to set the 'limiter'. This limits the auto focus range from infinity to 52cm or from 38 to 52cm. When doing macro jobs, I nearly always set the lens in the manual mode. This is easy using the switch on the lens. The manual rotation from infinity to 38cm is 270 degrees. This is more than enough to be able to manually focus with extreme accuracy. The AF of the Canon 5D Mark 2 can be adjusted per lens. The problem of front focus and back focus has therefore become a thing of the past. That said; with my test sample I did not have to do so.
Sigma 150mm suitable as portrait lens or not?
All sorts of opinions about the ideal focal length at portrait photography are going around, just as is the case with macro photography. For a full frame, the 85 or 90mm is considered the most perfect lens for portraits. However, I don't find that enough for a tightly cropped portrait. Usually I work with a 100mm f/2.0 in the studio. There are times when I would like to have a tad more mm at my disposal. This brings you to a 135mm or a 70-200mm zoom. I don't like running around in a studio environment with one of these large 70-200mm/2.8 'trumpets'. The Sigma 150mm/2.8 has a much more modest appearance and the option to focus closely will also come in handy for example at 'bodyscape', a different branch of fashion photography. I truly appreciated the 150mm focal length for working in the studio. A studio that is only lit by the setting light of the flash units, is slightly on the dark side, yet the AF of the Canon 5D Mark 2 was able to do its job quite well, in combination with the Sigma 150mm f/2.8.
Significant vignetting but little distortion
One of the disadvantages of a full frame camera is that many lenses suffer from heavy vignetting at maximum aperture. And the Sigma 150mm f/2.8 is unfortunately not an exception. I measured vignetting at 2 steps at aperture 2.8 and the distance set to infinity. This vignetting appears to be stubborn, even at 11.0, I run into the remainders of it. However, this is negligible in practice. If you set the camera to a smaller distance, vignetting becomes significantly less. Telephoto lenses are known for their little distortion. The Sigma 150mm f/2.8 again is not an exception, while distortion is not visible in practice.
Sigma macro lens test - Sharpness and contrast
The more than 20 million pixels of the Canon 5D Mark 2 only show to full advantage when combined with a lens that is crystal-clear and sharp. At aperture 2.8 the center can be used without a problem as became clear from the pictures taken in practice. One aperture step will provide high quality sharpness in the center. Even the edges are not disappointing. When editing the files, I noticed having to sharpen the files less than usual. The quality of the final print will certainly benefit from this. For a macro lens it is extremely important that intentional blur, for example a fore- or background is rendered with a nice and appropriate haze. Also in this area, the Sigma 150mm f/2.8 scores really well.
Sigma lens review conclusion
The Sigma 150mm f/2.8 is widely applicable in combination with a full frame camera, not only as a macro lens, but also as a portrait lens. Distortion is negligible, however; vignetting is significant. The auto focus works fast without 'hunting', although I miss a system to prevent blur caused by jitter. The lens is incredibly sharp from aperture 4.0 over the entire image field. This allows you to play with the depth of field. And isn’t that exactly what a full frame camera is all about?