Review Sigma 105 mm/2.8 EX DG OS HSM Macro (C APS-C)

The Sigma 105 mm 2.8 OS Macro has entered the market in the summer of 2011. A big difference with the previous model is the built-in image stabilization. The focal length of 105 mm is sometimes a bit tight on a full-frame camera in macro photography; you are often working in your own shadows then. In this regard, a 150 mm or a 180 mm macro is preferred. A focal length of 105 mm is very useful as a portrait lens in many cases. And if you enjoy working with primes, the Sigma 105 mm 2.8 Macro OS is a logical step after a 50 mm standard lens. The actual price at the moment is much lower than the suggested retail price at its introduction, which makes this Sigma macro lens even more attractive.

Construction and Autofocus The lens is made of a high-quality type of plastic, and the mount is made of metal. Sigma fortunately does not use the delicate hammered motif anymore. The focus ring turns completely free of play and with just the right friction. The stroke is about 180 degrees. The whole feels very solid and the lens is supplied with two large lens hoods: one to use with a full-frame camera and one to use with an APS-C camera. The AF is driven by a USM motor. Focusing with a Canon 5D MK2 is not very quick; from 15 meters to 1.5 meters in 0.32 seconds. That is a fraction more than the USM-powered Canon 100 mm 2.8 IS Macro. Focusing makes some noise and in low contrast, the AF sometimes shows seeking behavior.	{insertgrid = 289}

Image stabilization
The image stabilization provides a gain of approximately 3 ½ stops. The lens becomes so much more versatile because of that. At a focal distance of about 33 cm, the effectiveness is approximately 1 stop. A similar phenomenon also occurs with the Canon 100 mm 2.8 IS Macro. The image stabilization of the Sigma makes an occasional grunting sound, long after the image was taken too.
Vignetting Sigma 105 mm macro
Vignetting, expressed in stops, is very low at all apertures. Even at full aperture you will not have to take it into account in practice. Quite an accomplishment for a full-frame lens.
Distortion Sigma 105mm macro The distortion is extremely low, namely -0.12%. This will never be visible or distracting in practice.

Bokeh
As you can see in the Sigma 105mm macro sample image above, blurred elements in the foreground or background are common and thus important in macro photos. We see that the Sigma displays that blur very nicely woolly.
f/2.8	f/2.8
Flare
In backlight, the flare is not so bad; this is less than with the Canon 100 mm 2.8 IS Macro.
Resolution Sigma 105 mm macro
The resolution, expressed in lines/sensor height, exhibits good values. Stopping down only once is needed to achieve a high peak. The difference between the center and corners is very small which is advantageous. The resolution at f/11.0 is hardly less than at f/8.0. With macro, it is sometimes necessary to stop down in order to get enough depth of field. A lens that draws sharply.
Sigma 105 mm/2.8 EX DG OS HSM Macro, coner f/5.6	Sigma 105 mm/2.8 EX DG OS HSM Macro, center f/5.6
Chromatic aberration
The chromatic aberration is low and also in this area, the Sigma performs very well.
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Conclusion Sigma 105 mm/2.8 EX DG OS HSM Macro review
	See our overview of tested lenses or our overview of tested lenses with a Canon mount to compare the performances of this lens with other lenses.
WYSIWYG score: This table shows the performance of this lens if you store the files in the camera as jpg, where you have all available in-camera lens corrections applied. This score gives you for this lens/test camera combination: “What you see is what you get”.	{insertgrid=308}
Pure RAW score: This table shows the performance of this lens when the file is stored in the camera in RAW format. This score approaches the intrinsic quality of the combination of lens and test camera.	{insertgrid=309}
Pros High resolution Minor difference in resolution between the center and corners Beautiful bokeh Very low distortion Effective image stabilization at normal focal distance	Cons Sensitive to flare Tendency to hunt at low subject contrast
If you’re looking for a lens with the highest image quality for a Canon APS-C camera at an attractive price, seek no further: the Sigma performs very well. For example, distortion and vignetting are low and, important in macro, the bokeh is beautiful. Two small remarks, after a long search. The autofocus sometimes searches in low contrast. And the resistance towards flare is less compared to the current Sigma Art lenses. The Sigma 105 mm 2.8 OS Macro is cheaper than the Canon 100 mm L 2.8 IS Macro. This one has a slightly higher chromatic aberration, is more sensitive to backlight and doesn’t deliver a higher resolution.