When the Sony Alpha 100, our 2006 Camera of the Year, debuted last year, the only optics available for it were cosmetically updated Konica Minolta lenses. At the time, Sony promised a future line of Zeiss-designed glass. This 16- 80mm f/3.5-4.5 ($660, street) -- a vaunted T*, no less -- is the first of the promised line to run the Pop Photo Lab gauntlet. How does it compare with Sony's similar but less expensive 18-70mm f/3.5-5.6 kit zoom ($190, street)? Let's see.
The Zeiss is an ounce or two heavier than average. Zoom and distance scales are well marked. The zoom action is somewhat uneven, growing slightly stiffer as the lens is racked out; the MF ring is among the roughest-turning we've used recently. Autofocusing on the Alpha is slightly noisy and more sluggish than average.
In The Lab
As expected, SQF data showed Excellent sharpness and contrast at the three tested focal lengths. DxO Analyzer 2.0 tests found Visible barrel distortion at 16mm (0.57%), and Imperceptible pincushion distortion at 35mm and 80mm (0.09% and 0.10%, respectively), nearly identical to the kit lens. The Zeiss lens showed no light falloff in the corners by f/8 at 16mm, and by f/5.6 at 35mm and 80mm -- about average and, again, same as the earlier lens. At the uniform close-focus distance of approximately 12.75 inches, the maximum magnification ratios ranged from 1:14.25 at 16mm to a satisfying 1:3.8 at 80mm. (The less expensive Sony kit lens offered more magnifying power, 1:3.26 at 70mm.)
Is the Zeiss upgrade worth the extra $470? For many, yes. It's marginally faster, with a significantly wider zoom range, and the construction is all-metal instead of plastic. More importantly, while both lenses tested in the Excellent range, the Zeiss's numbers were an order of magnitude better, especially at higher magnifications, due to better control of chromatic aberration. DxO tests found less than half the color fringing in images from the Zeiss compared to those from the kit lens. Depending on your subject, that can mean visibly improved sharpness.
Click here to see a gallery of images taken by the Sony Zeiss 16-80mm f/3.5-4.5 Vario-Sonnar T* AF.