Medium Format Lenses with the Pentacon Six Mount
A comparative test
by TRA

The teleconverters


There are at least three 2× teleconverters in the Pentacon Six mount:

Arsenal also manufactures a 1.4× teleconverter which has the advantage of only reducing the amount of light reaching the film by the equivalent of one stop, while 2× converters reduce the amount of light by two stops.  (This is not a fault, but a consequence of the way light rays behave when magnified.)

I have compared the three 2× teleconverters with each other and with the Vivitar 2× teleconverter manufactured in the Hasselblad mount.


[C372-26A: three 2× converters with Pentacon Six / Exakta 66 / Kiev 60 mount, plus a Vivitar for the Hasselblad 500C
Front right is the Arsenal 1.4× converter]

The Vivitar 2× converter for the Hasselblad stands out immediately as being much bigger and heavier than the other converters.

However, it is the shape of the Schneider 2× converter that is most different from the other three. As with the Carl Zeiss Oberkochen 2× converter for the Hasselblad, the front element of the Schneider converter is mounted at the end of a narrow tube a long way forward of the front mount of the converter. This means that it protrudes into the back of the lenses with which it is used, resulting in some compatibility problems. Although the Exakta 66 manual says that the 2× converter can be used with the 80mm lens, this is not the case (I am sure that the manual was written before the converter was manufactured). As later Exakta 66 literature states, the Schneider 2× converter can be used with (Schneider) lenses from 150mm on up. It can be used with very few Carl Zeiss Jena or Arsenal lenses, as they mostly have a rear element that is right at the back of the lens – although it works well with the Pentacon 500mm lens – see the section on 1000mm.


[C308-17: Close-up of the rear of the Carl Zeiss Jena 300mm f/4 Sonnar lens.

The rearmost element of this lens is only just below the mount, and the Joseph Schneider 2× converter cannot therefore be mounted on this lens.
The fork-shaped connector at 11 o'clock in this view engages with a pin in the Pentacon 35mm adapter, transmitting the aperture selected on the lens via the EDC contacts on the adapter to the metering circuits in Praktica LLC, PLC and VLC cameras.]

To go back to the section on adapters, click here.

To see in detail how the Schneider teleconverter transmits the aperture information to the Exakta 66 TTL meter, click here.

The 2× Kiev converter is much sharper than the Panagor. The Schneider 2× converter is excellent, as is the Vivitar 2× converter in Hasselblad mount.

If you just want to see results obtained with the 2× converters, see parts of each of the following sections:

160mm     240-300mm   500-560mm    600mm    1000mm

If you prefer to work through the whole lens test without missing anything out, click below to go on to the next section.  You will also see the results obtained with the 2× converters at the appropriate points.
Next section (120-140mm)

To go back to the beginning of the lens tests, click below and then choose the focal length that you want to read about.
Back to beginning of lens tests

Home

© TRA January 2002, November 2005