Bright-Line View- And Rangefinder - Leica M-E Anleitung

brighT-LiNe view- aNd raNgeFiNder

The Leica M-E's bright-line view and range finder is
not only a very high-quality, large, brilliant and bright
viewfinder, it is also a highly accurate range finder
coupled to the lens. It has an enlargement factor of
0.68 x.
The size of the bright-line frame is optimized for the
full format of the Leica M-E and thus corresponds
ap proximately to the sensor size of 24 x 36 mm
a distance setting of 1 m. The bright-line frames are
linked to the distance setting in such a way that paral-
lax error - the misalignment between the lens and the
viewfinder axis - is automatically compensated. The
bright-line image and the picture are practically iden-
tical over the entire distance setting range of 0.7 m
to ∞. Practically identical means that at distances of
less than 1 m the sensor records slightly less than is
displayed by the inner edges of the bright-line frames
and records slightly more at longer distances (see
adjacent graphs). These slight variations, which are
rarely significant in practice, are due to the operating
principle:
The exact format is 23.9 x 35.8 mm, corresponding to the usable
1
format of analog Leica M models.
Bright-line frames on a viewfinder camera must be
adjusted to the angle of view of the relevant lens focal
lengths. However, the nominal angles of view change
slightly when focusing – due to the changing extension,
i.e. the distance between the optical system and the
sensor plane. If the set distance is less than infinity
(and the extension is correspondingly larger), the
actual image angle is also lower and the lens records
1 with less of the subject. In addition, the image angle differ-
ences are greater at longer focal lengths as a result of
the greater extension.
B
A
A Bright-line frame
B Actual image field
Set to 0.7 m: The sensor records approx. one frame width less.
Set to 1 m: The sensor records exactly the image field dis-
played by the inner edges of the bright-line frame.
Set to infinity: The sensor records approx. 1 (vertically) /4 (hori-
zontally) frame width(s) more.
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