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THE HARPER 16mm FILM PROJECTION SYSTEM
AN UNUSUAL PREWAR CINE DEVELOPMENT
BY ALAN E. LOTT

From the earliest days of the cinema various standard. These films, to DIN standards, could
inventors have produced different film gauges be projected on machines built to SMPE
and systems, sometimes to circumvent patents, specifications by revering the films laterally in
sometimes to try and make improvements in the gate and then placing a reversing prism in
picture quality and/or sound reproduction. front of projector lens to reverse the image to
According to Rogge, Re£ 1, a hundred years of show correctly on the screen. (The 17.5mm and
cinema has yielded almost one hundred film 9.5mm S.O.F. systems developed primarily for
formats. An interesting and informative account horne use during the mid to late 1930s are
of many of these is given in Ref 2. Most of considered to lie outside of the context of this
these have long since been consigned to article).
oblivion.
Once 16mrn S.O.F. had been demonstrated to
The origins of narrow gauge (I hate the be a practical proposition it quickly became
description sub-standard) non-theatrical and used by traveling showmen, schools, industry
amateur films go back to 1912, the year when and science as well as home entertainment for
28mm was the first gauge to use the new non- the small number of the more affiuent members
inflammable tri-acetate film base invented of society. It was also used extensively during
simultaneously in France and the USA. Ten World War Two by the various armed services
years later in 1922 9.5rnrn was launched by to all combatant powers for training and
Pathe Freres to be followed six months later in entertainment of the troops.
1923 by 16rnm developed by Eastman-Kodak
in the USA. However, during the early days of 16mm S.O.F
in the 1930s, although acceptable for many
Commercial/theatrical 3 5 rnn sound-on-film purposes, the sound quality left much to be
became firmly established in the period 1927- desired. Film manufacturers were struggling
30 whilst development commenced in 1927 to with emulsion problems because of the
achieve acceptable sound-on-film on 16 mm. considerably different characteristics required
The first projector for 16mm S.O.F. was Model for optimum picture quality and optically
PG.30 manufactured in 1930 by the Radio reduced, or re-recorded 35mm sound tracks.
Corporation of America, Re£2. Printer and recording optics were not coated to
reduce flare and amplifiers were basically crude
A proposed standard for l6mrn S.O.F. (1932) with large thermionic valves. The concept of
was published in the Journal of The Society of negative feedback was still a novelty and not
Motion Picture Engineers (SMPE) in November always fully understood or used. The struggle to
1932 and is reproduced on page 113 of Re£2. improve sound quality on 16mm led to many
This was adopted by the American Standards different recording systems from unilateral
Association in 1935. This progressively became variable area to bilateral variable area to
accepted as an international standard enabling variable density to name only three.
16mm "talkie" films to be distributed and
shown in virtually every m~jor country. Initially Enter Martin Harper, an employee of the Miles
Germany adopted a similar standard but with Aircraft Company of Woodley, Reading,
the optical sound track and perforations on Berkshire. He reasoned that the quality of
opposite sides of the film to the American 16mm S.O.F. would be considerably improved