of Photogrammetry
ion with the expe-
all Zeiss Autograph
ployed but only a
d. Plotting is done
3 and 1951.
erland reported no
ngineering surveys.
le survey by these
the method to 1:
C.
tography affecting
$, etc.
e still very widely
hole each country
oward wide angle
10t appear to have
cameras with nor-
of Florence (San-
. of Paris (S.O.M.-
d 19 X 19 em, F =
ivilliers); the Swiss
m).
ns and for certain
; F5 125 mm, to
the map is to be
in these regions.
urveys in the Bel-
cm, f — 165 and
| or they use glass
art already made
X 9 inches (23 X
1etimes 5.2 inches
(345)
Zeiss cameras of various types, all for 30 X 30 cm film, f = 20 cm, or 18
X 18 cm, f = 10 cm, Topogon lens.
S.O.M. - Poivilliers cameras for plates, f = 125 mm, 19 X 19 cm, or for
film (of the same format);
The Italian Santoni IV camera for film, f = 135 mm, 18 X 20 cm;
The Italian Foma cameras for film, 93/B (f — 210 mm, 30 X 30 cm) and
93/A (f = 125 mm, 18 X 18 cm). |
The wide-angle English Williamson cameras OSC-MK 1 of 6-inch focal
length used in Canada.
As newly made cameras, we find
The Zeiss “Pleon-Kamma”, 18 X 18 cm, f — 7.5 cm, equipped with the
novel Pleon lens.
The new Wild camera, 15 X 15 cm, f — 100 mm for plates and equipped
with the Aviogon lens.
Multiple-lens cameras.
The great majority of the photogrammetric organizations use vertical
photographs exclusively.
Several instances where multiple cameras are used should be cited:
In Italy: the double Santoni camera using plates 13 X 18 cm, f — 195mm,
mounted 30? from each other, with their axes inclined 15? from the
vertical transversely.
The triple Santoni camera using film, one camera vertical, two cam-
eras inclined laterally at 48°.
In the United States: the Twinplex assembly having two cameras inclined
20? from the vertical, either transversely or longitudinally.
The Trimetrogon assembly with (one camera vertical and) two cameras
inclined 60? laterally.
Finally the U.S. Coast and Geodetic Survey uses a ninelens camera.
Conditions in taking the photographs.
Speaking only of the much more numerous verticai photographs, overlap
on the line of flight varies little from one country to another: 55 to 65%.
Average overlap between flights varies from 10 to 3096; even 35% in Germany;
35% in Canada; 40% maximum overlap was reported by the Belgium Minister
of Public Works and in The Netherlands. The scales of the negatives are very
variable in accordance with the plotting method and established scale of the
maps, and for a given scale they vary in different countries.
Emulsion, exposure, filter, etc., are reported in detail by Commission I.
Generally panchromatic emulsions are used with an infrared emulsion used only
in special cases. There were also trials and research with colored emulsions.
III. Plotting processes using rectification.
The processes of rectification are utilized only for special and urgent work
which does not demand extreme precision in areas of much relief. In countries
having large flat areas it is used for standard maps.
This process is not used in Austria, Canada or Switzerland. In France the
