Zeiss Dimension Manuel D'utilisation page 25

Entrance pupil (EnP)
The position of the entrance pupil (2) is indicated on each ZEISS
Dimension lens. Thus, it is possible to position the lens for uses
in which the center of perspectivity has to be exactly aligned.
The exact position is, depending on the focal length, indicated
by a line above or under «EnP» or by an additional distance
specification indicating how far the position is located from the
engraved line.
ZEISS Dimension 2/12:
ZEISS Dimension 2/35:
US
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