Page 18 - RD_2015_12

tained from the wider film. On one or two slightly at fault, the defect becomes intensi-
occasions the gauge has been revised slightly, fied still more. By the time the picture reach-
but the variations merely affected the dimen- es the projector the infinitesimally small
sions of the hole to a microscopic degree. defect in the first instance becomes in-
Fundamentally, the gauge as set by Edison for creased fourfold or even more. The picture
the first commercial apparatus for showing will jump and flutter in the most distressing
photographs in motion prevails to-day, and is manner, and no matter how dexterous the
universally accepted. operator may be, and despite the excellence
of his projector, he cannot by any means
The film is received from the manufacturers rectify or mitigate very appreciably defects
in a plain ribbon, and the perforation has to arising from indifferent perforation.
be done shortly before the film is taken in
hand for exposure. The film manufacturers The contribution of imperfect perforation to
cannot possibly supply it perforated, because unsteadiness in projection was recognised in
the celluloid base undergoes continuous the earliest days; and great technical skill was
physical change while in storage. Under vary- devoted to the elaboration of machines to
ing climatic conditions it shrinks and expands puncture the film with scientific precision.
to an extent which may not be observable to Marvellous appliances have been produced
the eye, but becomes pronounced when the for this purpose; but despite the infinite la-
picture is projected upon the screen. bour bestowed upon their production the
possibility of error is ever present. Still, it has
The necessity for mathematical precision in been reduced to infinitesimal proportions,
the matter of perforating is somewhat ob- and, given a careful operator, a film can be
scure to the uninitiated, but its effects may perforated with the holes varying not a thou-
be demonstrated very easily. Compare the sandth part of an inch from the gauge.
vibrating or oscillating flickering picture of The very earliest type of perforating machine
1896 with that shown upon the screen to- was known as the “Rotary Perforator," Paul
day, in which the effect produced comes very leading the way in this, as in several other
close to that of the camera obscura. If the ramifications of the industry. The machine
perforation errs the hundredth part of an was driven by a mechanism identical with
inch, steadiness in the picture
is forfeited. The films have to
be punctured with the same
mathematical accuracy that
goes to the production of a
tiny screw intended for the
most delicate piece of mecha-
nism.
This is especially the case in
regard to the perforation of
the negative film. If this is not
absolutely true to gauge, the
existing error will be magnified
in the passage of the film
through the camera; and
should the latter be ever so

18 REEL DEALS December 2017