jein
lies dir mal den Beitrag von luisalegria durch:
sieht dann so aus:This is an interesting device. Its a telephoto adapter but with a variable focal length- a very early zoom lens. It also had multiple ranges of focal lengths depending on how it was combined with the base camera lens.
It can be used by itself, it just has a very long focal length, I have tried mine.
This can also be used by replacing the front cell of a tessar type lens on its shutter.
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