Sony has a number of lenses in its Alpha system that can be used as the everyday lens that spends most of its time on an APS-C DSLR. The DT 16-80mm f/3.5-4.5 ZA Vario-Sonnar T* Carl Zeiss lens. This is the highest quality standard lens offered by Sony. As denoted by 'DT', this lens is designed to work with the DSLRs with APS-C image sensors only.
The DT 16-80mm f/3.5-4.5 Vario-Sonnar lens has the following features:
- 5x optical zoom with 35mm equiv of 24-120mm
- Circular aperture
- T* coating for higher light transmission and minimal flare and ghosting
- Plastic light weight build
There is no image stabilisation built into the lens. As with all Sony lenses (and prior Konica Minolta) the image stabilisation is provided by the systems build into the Sony camera bodies. This method does not always make the lens cheaper or smaller than similar lenses with built-in stabilisation but it does mean that any compatible lens attached to an Alpha camera body will automatically benefit from the cameras image stabilisation feature. As always when needs be the tripod can always be resorted to.
The DT 16-80mm lens does not have in body AF system like SSM or SAM technology and so is reliant on the in body motor of the DSLR it is attached to for the autofocusing. Autofocusing is generally smooth across its range. The focus ring does not rotate during autofocusing.
The focal range of 16-80mm (24-120mm 35 equiv.) made the lens ideal for tackling a range of everyday situations and a great general purpose travel lens.
Focusing on the a700 and a350 was swift enough for most purposes although as expected the a700 focused the lens faster. Focusing accuracy was highly dependant on the DSLR body used
The lens aperture value increases with the focal length as follows:
- 16mm (24mm) : f/3.5
- 20mm (30mm) : f/4
- 35mm (45mm) : f4.5 (until 80mm)
The lens produced images with plenty of detail across its range on both the a350 (14mp) and a700 (12mp).
The lens contrast was high producing images with vibrant colours and depth. Images captured in RAW format and processed through the supplied software look quite dynamic.
Flare was never seen as a problem when a strong light source was out of the frame and ghosting was never seen as an issue.
When shooting with a DSLRs built in flash and the lens set to its shortest focal length the lower part of a scene will be in shadow due to the light being obscured. Removing the lens hood helps but it was often found just better to used an external flashgun.
The lens initially did not suffer from zoom creep but with continuous use in very hot tropical conditions this change. The 16-80mm lens obviously did not take too kindly to being heavily used in temperatures well in excess of 30 degrees Celsius. This is not a problem noted before on previous A-mount compatible lenses like 24-85mm f/3.5-4.5 and the 24-105mm f/3.5-4.5 Minolta lenses. It is possible the sample lens was defective in this regards as there have certainly been sample problems with the DT 16-80mm lens with the initial production run. Anyway, it is worth keeping this issue in mind if this lens is to be heavily used under very hot climatic conditions.
The Plus Points
- High contrast and saturated images
- Relatively fast at the telephoto end
- High sharpness across its focal range
The Negative Points
- CA higher than expected at 16mm
- High barrel distortion at 16mm
- Vignetting at 16mm
- Build quality could be better for this calibre of lens
The DT 16-80mm ZA Vario-Sonnar T* lens produced great looking results despite its weak points listed above. The results speak for themselves. The optics were definitely aimed at pleasing the more demanding enthusiast or pro photographer but the build quality did not instill the expected confidence that a Zeiss badged lens should give. Its build is not in the same league as the other Carl Zeiss lenses in the Sony range.
In the end its the optical qualities that matter the most and on the whole this is where the lens delivers. Lenses on the whole tend to have a much longer life span than the cameras they are used on so the 16-80mm lens is likely to be around for some time. It would be nice to see an upgraded lens with improved construction.
For travel purposes the 16-80mm lens pairs up with the 70-300mm G SSM lens. Between the two lenses a high optical quality can be achieve from 16-300mm with a wide enough focal range for most situations.EA