The Sony 24-70 mm 2.8 is a lens designed by Zeiss and already for sale since 2008. The blue Zeiss logo is put clearly visible on the side of the lens. The Zeiss mention and the high price ensure you expect the highest quality of this lens. Let’s see if Sony delivers.
Sony Vario-Sonnar® T* 24-70 mm/2.8 ZA SSM, @ 24 and 70 mm.
The three-times zoom range of the Sony 24-70 corresponds to a zoom range of 36-105 mm of a zoom lens on a camera with an APS-C sensor in practice.
Construction and autofocus
The Sony 24-70 mm 2.8 weighs almost a kilo. This is normal compared to similar lenses of Canon and Nikon. A great deal of glass is required for this intensity to be achieved on a camera with a full-frame sensor, for which this lens is designed.
The lens gets longer as you zoom to 70 mm. Remarkable is the AF switch on the side of the lens, which rotates in place of sliding.
The lens focuses quickly, thanks to high light intensity and the SSM (SuperSonic AF Motor), even in the dark, without hunting. Focusing is quiet but not silent.
With Sony, image stabilization takes place on the sensor instead of in the lens. This has the advantage that you can use image stabilization with all lenses (“Steady Shot,” Sony calls it) and it works well.
During the image stabilization test with a focal length of 70 mm, it showed that only at a shutter speed of 1/200 second there is no further improvement by turning on image stabilization. At 1/100 second, the effect is measurable, but not visible in practice. From 1/50 second, the improvement in sharpness becomes visible to the naked eye too thanks to the image stabilization.
The Sony Zeiss 24-70 mm lens scores perfectly in terms of vignetting. In practice, you will almost never encounter vignetting if you use this lens on a camera with an APS-C sensor.
Despite the fact that the in-camera distortion correction was turned on at the Sony A77, the jpg files of the Sony 24-70 show visible distortion, especially in wide angle. The automatic compensation of distortion in the camera apparently has no effect here (yet?). In particular at 24 mm, the distortion will be visible. Fortunately, it is easy to correct distortion with software afterwards.
The Bokeh of the Sony 24-70 mm is not bad, but also not very good. It seems a bit restless. In the example, you can assess the Bokeh and the sharpness of the plant in the foreground at 100%.
The Sony 24-70 is not bothered much by flare if you ensure that no bright light source is shining directly into the lens and you use the lens hood. If this occurs, you can be troubled by flare, as shown in this practical example.
The resolution of jpg files created with the Sony 24-70 on a Sony A77 camera is very high at all focal lengths and apertures. That is a top performace. It is striking that the resolution of the corners is not at the ends of the zoom range (24 mm and 70 mm), but slightly remains behind the center in the middle of the zoom range (30 to 50 mm). From aperture 4, the resolution across the entire zoom range in the extreme corners does not come below the 1500 LW / PH, and in the center not below the 2000 LW / PH. This difference can not be seen with the naked eye in practice.
With this lens you will never suffer from chromatic aberration. Chromatic aberration is low at all focal lengths. Very good.
Conclusion Sony Vario-Sonnar® T* 24-70 mm F2.8 ZA SSM review
- Optical top class quality (resolution, chromatic aberration and vignetting)
- Solid as a rock
- Heavy: almost a kilo
- Visible distortion at 24 mm
- High purchase price
In terms of construction and optical qualities, such as resolution, chromatic aberration, and vignetting, this lens certainly makes worth its high price. This lens is among the finest lenses for cameras with an APS-C sensor. Distortion, especially at the ends of the zoom range, is not (yet?) corrected by the camera.