This virtual tour of the Curzon Collection
is a selection from over 200 items on display in the cinema.
PATHESCOPE KOK 28mm
This machine is a beautiful piece of projection engineering
from 1912. Pathe-Freres introduced the 28mm film gauge
to avoid the use of nitrate based 35mm film stock in use
for ‘home cinema’ use at that time.
This projector ensures further
safety by providing the energy for the light source by
the use of a dynamo driven from a flywheel connected to
the Main drive shaft. Turning the handle whilst projecting
the film therefore provided the energy for the lamp which
is 6v. 0.75watt. This provides a steady 30 inch picture.
The projector is fitted to a wooden base and has a capacity
of 400feet of film which, depending on the projectionist,
gave up to 12 minutes running time at 16fps.
Construction of the KOK is
on a cast central frame and to which all of the, mechanism
is mounted. Great use of aluminium based casting is made
use of providing easy handling.
A single sprocket is used to drive the film to and from
the wide picture gate.
28mm FILM
The 28mm film gauge was used to avoid the use of nitrate
based 35mm film which was all that was available for ‘home
movie’ enthusiasts in the early part of the 20th-Century.
28mm film had one perforation o one side of the picture
frame and three on the other. The frame is full width
and so gave a respectable large image only slightly smaller
than 35mm. with an image size of 19mm x 14mm. There are
20.5 frames, as opposed to 16frames on silent 35mm, which
realised a 400ft. of 28mm film being equal to over 500ft.
of 35mm. Printed 28mm films were optically reduced from
35mm originals which meant they were issued as complete
films and not edited. By 1920 over 2000 films were available
rent or for sale at the old twopence per foot.
The picture gate of the KOK
showing the easy of access and its wide opening. The intermittent
is by a claw which rides back gently on the surface of
the film as it returned. There is a single shutter blade
which rotates in front of the picture gate which is enclosed.
Note also the terminals on the brass lamp house and the
leads which come from the dynamo.
The drive
arrangement of the KOK and the feed and take-up spool
arrangements The belt drive from the dynamo to the flywheel
can also be seen.
