ECLAIR ACL I Camera, Руководство пользователя

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Lens Mounts. ‘C’ mount, lenses, as well as other
professional mounts such as ‘CA’, Arriflex etc. may
be used on the ACL. The mechanical back focal
distance for these other lenses is- therefore greater
than 17.52mm. The mount is designed like a flange
of which the internal thread matches the ‘C’ mounts
and the external thread matches the Eclair ‘TS’
mounts. Correct orientation of each lens is ensured
by a slot at the top of the flange.
The gelatine holder. Each ACL camera is supplied
with a gelatine holder, which is positioned between
the ‘C’ mount and the reflex mirror, (fig. 1)
The advantages of this design are -.
1. It is not necessary to change the filter at
each lens change.
2. It is easy to check the presence and type
of gelatine through the viewfinder.
3. It is not necessary to have different filters
for different lens diameters.
The oscillating mirror. A reflex image is achieved
by means of the oscillating mirror travelling at half
the frame speed. The image formed by the lens is
transmitted on to the ground glass during the de-
scent of the film. The reflecting surface of the mirror
is glass fixed to a magnesium support.
The plane shutter. In the ACL, unlike other reflex
cameras where the mirror is also used as a shutter, a
large diameter, plane shutter having an exposure
angle of 1.750 operates in front of the film. The
shutter cuts off the image in the direction of the
smallest dimension, i.e. from top to bottom, and is so
shaped to ensure an even exposure.
The ground glass has three engravings:-
1. For academy motion picture format
10.20 x 7.42mm.
2. For TV format 8.41 x 6.30mm.
3. A cross denoting the centre of the two
formats.
F I G . 4 . E M B A S E U N I T C I R C U I T D I A G R A M
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