Carl Zeiss Distagon T* 25 mm f/ 2.8 Z
- focal length 25.7mm
- angle of view through diagonal/width/height: 80,2°/70°/50°
- coverage at minimal distance: 85 х 56 cm
- aperture step: ½ stop (except 16-22)
- filter diameter: 65 mm
Carl Zeiss Distagon T* 25mm f/ 2.8 Z – Precise focusing mechanism with a long run of a focusing ring provides a very accurate focus adjustment. Zeiss T* multicoating provides reflexes and flare reduction and good color reproduction. Almost round diaphragm provides a nice bokeh.
Very rigid and durable fully-metal barrel made of brass with a chrome-plated bayonet. Front element doesn’t rotate during focusing. Focusing length data is not transferred to the camera. DOF scale is painted on the lens barrel for the specific aperture values being set. This lens was developed in Germany but manufactured by Cosina (www.cosina.co.jp) in Japan under the Zeiss quality control.
There are several mounts for Carl Zeiss Distagon T* 25mm f/ 2.8 Z
ZE – for EF (Canon) bayonet
ZF – for F (Nikon or Fuji) bayonet
ZF.2 – for F with a chip (Nikon or Fuji) bayonet
ZK – for K (Pentax or Samsung) bayonet. Manufacturing of this line stopped in September 2010
Features of Z-type lens with different bayonets:
ZE-type – aperture adjustment is possible only with camera controls. Manual aperture control ring is absent. All camera modes P, Tv, Av, M and focus confirmation are fully working. Focusing distance and aperture values are transmitted to the camera. Some functions of autofocusing lens (A-DEP, scenes) are not supported.
ZF-type – lenses with a manual focusing without a chip and are equipped by AI aperture interface. Exposure metering and control is possible with all appropriate cameras.
When using this type of lens with cameras without AI interface you’ll get a closed diaphragm up to the preset value but metering and automatic control of the diaphragm will not possible.
ZF.2-type – manual adjustment by the ring is possible as well as a camera adjustments (you’ll have to set diaphragm manually to the maximum value which is marked by orange color and camera will work in all automatic modes). For cameras that don’t have electronic interface diaphragm adjustment will be possible only by manual preset.
ZK-type – lenses with a manual focusing which correspond to KA-standard.
Additionally lenses are equipped with electric pins.
Besides diaphragm ring may be blocked in automatic mode (green “A”). Thus exposure control and other parameters adjustment (time, aperture and program mode) are possible with these camera types.
ZS-type - lenses with only manual focusing. Equipped with an aperture closing pin. There is a M-A switch for changing a manual mode to automatic.
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Posted by: dv Date of publication: 29.09.2010