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Stand 215 —cont.
Activities and Products
Finnmap Engineering Company performs geodetic operations, photo-
grammetric mapping and regional as well as town planning. The company
is the biggest in Finland and is interested in corresponding activity abroad.
The company is equipped with modern and effective instruments such as
Wild and Zeiss geodetic instruments, Tellurometer, transportable triangu
lation towers, Wild autographs with automatic registration of coordinates
and the profiloscope, IBM 610 electric computer, etc.
The highly qualified and experienced personnel has enabled the company
to carry out various achievements from city survey of high accuracy to
helicopter-carried Tellurometer traversing far beyond the Arctic Circle.
Grant Production Co. Ltd. STAND 216
4 Rathbone Place, London W.l Students Union
Malet Street
Representatives: F. Mansell Third Floor
J. D. Pollard
J. P. Larard
Exhibit
The Survey Model Grant Projector is primarily a visualising equipment
designed to provide a brilliant image, enlarged or reduced, which can be
viewed, traced, or photographed.
For the detailed and accurate study of aerial photographs a special copy-
holder is provided incorporating a tilting mechanism to permit rectification
of errors caused by the angle of photography, ground configurations and
obliquity of view outside the photographic axis.
An alternative copy board is provided for larger originals such as plans or
maps. Two lenses are available to cover a full range of enlargement or
reduction from same size to 5 : 1.
Activities and Products
Grant Production Company Limited, the exhibitors of the Survey Model
Grant Projector, are also the manufacturers of the following products:.
(1) The Standard Model Grant Projector—a visualising equipment in
general use throughout the advertising and commercial art field.
(2) The Photoprojector—a vertical camera for producing photoprints, as
well as line and half tone negatives for small offset litho work.
(3) A range of platemaking equipment for printing down offset litho plates.
(4) The Mervac Presensitised Plate—a grained litho plate coated with a light
sensitive resin of exceptional stability under varying climatic conditions.
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Wallace & Tiernan Limited STAND 217
Power Road, Chiswick, London W.4 Students Union
Malet Street
Representative: J. T. Furness Third Floor
Exhibit
The W & T Alticorder. Lightweight portable photographic unit housing
a W & T Altimeter or Barometer. Unit contains an electrically driven
timer of low battery consumption permitting five days’ unattended opera
tion at one exposure over five minutes. Purpose of unit is to allow base
stations to be established with minimum of manpower.
Aneroid Barometers type FA-\29P and FAA26P. W & T Precision
Barometers in portable carrying case. Available in ranges 22-31-5 in. Hg
giving accuracy of 0-5 millibars for FA-126P and any 3 in. of mercury with
accuracy of 0-3 millibars for FA-139P.
Aneroid Altimeter type FA-181. W & T Altimeter complete with carrying
case and equipped with sling psychrometer. Available in ranges minus
1000 to plus 3000 feet, minus 1000 to plus 6000 and minus 1000 to plus
16,000.
Kern & Co. Ltd. STAND 219
Aarau, Switzerland Students Union
Malet Street
Representatives: H. Yzerman Third Floor
R. Haller
R. Wahli
Exhibit
PG\-Stereo Restitution Instrument. The PG1 is a stereo photogrammetric
restitution instrument with optical reconstruction of the bundles of rays,
incorporating the following features: The Stereo-Direct-Inverse system
decreases the mean square error in height by an average of 50% and it
eliminates the errors caused by fixation disparity and Fertsch-effect. 1
Mercury vapour discharge lamps illuminate the field of vision of 6 in.
diameter at a projection distance of 25 ±4 in. so well, that it is not necessary
to install the instrument in a darkened room.
The Kernon 6-in. projection lens has a theoretical distortion of only
± 0-0015 mm.
1 The S.D.I., A New Method for Stereoscopic Measurements and
Plotting, Photogrammetria XII, 1955-1956, no. 4, page 287.
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