REPORT OF COMMISSION II: PLOTTING, THEORY AND INSTRUMENTS
7
Photogrammetric Equipment
In regard to the use of surveying cameras,
there is almost a unanimous preference for
the “wide-angle” camera type with a focal
distance of 11 cm. and 15 cm. and a film or
glass-plate negative of 18X18 and 23X23 cm.
The 21 cm. focal distance lenses seem to have
completely failed in present-day projects. As
for plotting apparatus, this consists for the
most part of instruments of the so-called
First-Order, due to the fact that the most
urgent need is for large-scale plans which are
expected to be used for projects requiring
high precision and as working plans. Although
surveying cameras, film and glass-plate sur
faces, and plotting instruments have under
gone only minor improvements, these have
made it possible to increase gradually the
ratio between plotting scales and photo
graph; whereas in those instances in which the
methods have not been greatly developed
from the theoretical point of view, we find
that an especially great progress has been
made in the use of these methods by means of
auxiliary instruments, such as electronic co-
ordinatographs, profiloscopes, etc., and the
utilization of results by means of electronic
computers. Here again efficiency and lower
cost are the principal considerations at
tributed more and more to these powerful
auxiliary instruments.
Resume
Until 1962, all photogrammetric activities
in Belgium were divided between State or
ganizations (public or military agencies) on
one hand, and universities and other educa
tional institutions, on the other. Recently,
private companies, and, more specifically,
their research departments, have begun
making use of photogrammetry and acquiring
the necessary equipment for this kind of work.
This spreading of photogrammetric activities
among private companies is explained by the
fact that after 1962 public agencies have been
assigning regularly the study of the lay-out
of automobile roads and the engineering
projects associated with them to the research
departments of private concerns, whereas in
the past these activities came under the juris
diction of state agencies. The result of this is
that the continuous research aimed at greater
efficiency and lower costs prompts private
companies to use rational methods for the
preparation of basic topographic plans. Inas
much as we are at the beginning of a new
development, we are not able to give, at this
stage, exact information in regard to the
photogrammetric equipment and the organi
zational system of these research bureaus;
consequently, we must confine ourselves to
stating that their immediate objective is to
prepare large-scale topographic plans (as a
rule 1:1,000) which are expected to serve as
ground work of projects. In view of what has
been said above, all photogrammetric activi
ties in Belgium at the present time may be
divided in three categories from the stand
point of the users of photogrammetry.
BRAZIL
Organization
industrial—Servicos Aerofotogrametricos
Cruzeiro de Sul S.A.
Activities
Aerial photography, photo-mosaics (un
controlled and controlled), photogrammetric
surveys at scales from 1:100,000 up to 1 :500.
Printing Department—correlated activities;
inventories of raw materials.
Personnel
Management, 15; Supervision, 10; Pro
fessional, 100; Technicians, 35; Servicing, 40.
Aerial Triangulation and Plotting
Instruments
Zeiss Stereoplanigraph (4); Santoni Stereo-
cartograph (1); Kelsh Plotter (2); Wild A9
(2); Wild Aviograph B9 (2); Coordinate
Recorders (1). (In addition to normal plotting
and aerial triangulation instruments.)
Aerial Data Recording
Zeiss, RMK 51/23, 153 mm., Pleogon,
23X23, 750-6,000; Wild RC5, 115/210, Avi-
ogon, 18X18, 1,050-1,575; Wild RC9, 88
mm., S. Aviogon, 23X23, 3,600-6,200; Fair-
child, 153 mm., Metrogon, 23X23, 1,530-
6,000.