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Pathe’s 9.5 mm Notched Title system

or how to get 20 minutes of runtime out of 30 ft of film.
Mike Trickett
One of the unique features of the Pathé Baby I can hear you asking how did they do it. Well
projector (and some later models) was the when the projector encountered a notch in the
notched film system. This ingenious system edge cut into the edge of the film, a small lever
caused the projector to pause and project a moved into the notched area, disengaging the
single frame of film when it encountered a claw mechanism and starting a worm drive
notch in the side of the film. This method of arrangement. As the operator continued to
displaying titles or stationary images saved on turn the handle, the worm drive moved a
film, and made the small 30 ft cassettes of film clutch mechanism to the end of its travel and
run for much longer that would normally be and reengaged the claw. A very ingenious
the case. little piece of engineering.
Of course Pathé took full advantage of the Of course, if the title or image required a
system, the more inter-titles or stills in the longer time to be read, then a second (or third)
film, the longer the running time. I have little notch, with its accompanying still image was
30 ft film in my collection titled A Visit to the added to the film.
Louvre, every painting displayed is only one
or two frames, together with explanatory In the 1930s Pathé introduced a number of
titles, it has a run time of over 20 minutes - not other projectors - the Lux was the only
bad for 30 feet of film! additional machine they produced which had
automatic de-clutching and re-engaging for
notched titles. This machine was motorized
and incorporated an 80 volt 40 watt lamp.
When the machine stopped to show a single
frame, a heat absorbing gauze shutter dropped
into the light path and although the image
became duller, the film was safe from
overheating.
Pathé continued to utilise the notch system in
later model projectors, these models would
stop when a notched title was encountered -
but required the operator to re-engage the
mechanism manually.
All of the films were printed down from
Pathé's 35 mm cinema releases; the quality
was generally very good, with sharp steady
images. Pathé had wisely designed their
9.5mm format to have the same aspect ratio as
regular (silent) 35mm film.

Left: Heavy line - First notch and corresponding
frame. Thin line – Second notch (if required,
depending on estimated time to read the first
title) and corresponding frame.

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