| Zeiss ZA Planar T* 85mm f/1.4 (SAL-85F14Z) on Sony NEX - Review / Lab Test | 
	| Lens Reviews											 - 					
						
						Sony NEX | 
| Page 1 of 2  Review by Klaus Schroiff, published March 2012
Special thanks to Dieter Scherk for providing this lens for testing! IntroductionThe Zeiss Planar T* 85mm f/1.4 ZA (Sony SAL-85F14Z) is certainly not an obvious choice for being used on the Sony NEX but if nothing else it is certainly an interesting experiment - especially using the new 24 megapixel sensor of the NEX 7. The Zeiss ZA 135mm f/1.8 may still be a tad better but it can certainly be taken as a benchmark lens.
The lens can be used on NEX cameras via Sony Alpha adapters. You can even use autofocus when using the Sony EA-LA2 adapter. Basically  it transforms your NEX into a Sony Alpha SLT. The setup with the Zeiss lens is a bit front-heavy for sure but I had no real issues with this - other may disagree with this view.
The NEX system has an APS-C format sensor so the ZA 85mm f/1.4 behaves like a "130mm f/2" on a full format camera. The "f/2" refers to the comparable depth-of-field at f/1.4. For determining the exposure, the real aperture obviously remains the relevant number.  
The build quality of the Zeiss lens is excellent thanks to an all-metal construction. The focus ring is decoupled from the AF gear so it does not rotate in AF mode. In manual focusing mode it operates very smoothly but there is a little play when reversing the focus direction - a characteristic shared with the ZA 16-80mm. The lens extends a bit at closer focus distances.
 
It isn't necessarily something bad but  the AF system of the Zeiss still relies on the classic focusing system driven by the camera (via a slotted drive screw) rather than Sony's modern SSM (supersonic motor). Consequently the AF produces a moderate degree of noise during operations. Due to the heavy weight of the lens system the AF speed is fine but not great. The combination of NEX-7 and EA-LA2 adapter worked flawlessly with the lens.  
  
    
    
  
| Specifications | 
|---|
 | Equiv. focal length | 128 mm (full format equivalent) |  | Equiv. aperture | f/2.1 (full format equivalent, in terms of depth-of-field) |  | Optical construction | 8 elements in 7 groups |  | Number of aperture blades | 9 |  | min. focus distance | 0.85 m (max. magnification ratio 1:7.7) |  | Dimensions | 82 x 73 mm |  | Weight | 640 g |  | Filter size | 72 mm (non-rotating) |  | Hood | metal, barrel-shaped, snap-on-type, supplied |  | Other features | focus stop button |  
 
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