TYFE OF PHOTO INTERPRETATION STUDY NUMBER OF PROJECTS 
(Continued) 
E. Miscellaneous Photo-Interpreta- 4 
tion Studies Re Sra 3 
(Note--Included here are such things 
as photointerpretation associated 
with legal cases, land-use and irri- 
gation studies ;photo-geologic and 
fracture analysis for petroleum ex- 
ploration; air-photo studies in the 
search for base metals and for in- 
dustrial minerals; drainage, hydrology 
and groundwater studies; planning 
(i.e. writing specifications)for air 
photography). 
TOTAL PHOTO-INTERPRETATION PROJECTS 
SINCE 1956 316 
The photographs used for this work are summer pan- 
chromatics at 1:15,840 on the prairies, and 1:31,680, 
and 1:63,360 farther north. The only equipment used 
was a pocket stereoscope. 
Mr. Angus Hills of the Ontario Department of Lands 
& Forests, with his staff, has been doing outstanding 
work in interpreting soil conditions in relation to 
tree growth. Their work has been done largely with 
summer panchromatic photographs at 1:15,8h0. 
Mr. D. Burger has reported on this in a paper referred 
to below. 
Geological interpretation of aerial photographs is a 
Standard technique in geological surveys of &ll kinds 
in Canada by Dominion, Provincial, and private agencies. 
The summer panchromatic photography at scales of 
1:15,840, 1:31,680, and 1:63,360 are most commonly used. 
W. G. Dean's study of the glacial features of the Clay 
Belt from aerial photographs is an interesting applica- 
tion of this technique. 
In Nova Scotia Dr. H. L. Cameron of the Nova Scotia 
Research Foundation has been obtaining very useful re- 
gional geological information using small hand-held 
cameras from a jet aircraft at 38000 to 42000 feet. 
Dr. Cameron has also been studying tidal currents 
from aerial photographs to provide information for the 
design of piers at Petit Passage and Ground Passage in 
Nova Scotia. The water area was photographed at 15- 
minute intervals from high to low tide, and from low to 
high tide. Current velocities were measured by a paral- 
lax method, and current directions plotted. This work 
will be the subject of a paper at the sessions of the 
Congress. 
Hunting Technical and Exploration Services, Apartan 
Air Services, and other commercial firme, interpret 
photographs for geological and soil data as a routine 
matter using R.C.A.F. small scale photographs or taking 
special photography as the job requires. 
  
Notes: 
(1) Published in the Photogrammetric Engineering 
Vol. XXV, (1) (March) 1959. 
Notes: Sweden Report: 
(2) Published in the Photogrammetric Engineering 
Vol. XXV, (5),(December), 1959. 
(3) Published separately. 
Notes: England Report: 
(1) See T. D. Weathered in "Shell Aviation News" 
January 1960. 
England: 
Dr. Frank Walker of the University of Bristol reports 
the following items: 
Interpretation of surface configuration and drainage, 
as distinct from the mapping of these features, has been 
largely associated with the work of the commercial com- 
panies in connection with resources surveys, irrigation 
projects, and drainage surveys. These have been carried 
out in Europe, Africa, the Middle East, and other parts 
of Asia. (1) 
The end product of interpreting surface configuration 
is inevitably closely allied to the problem of the re- 
presentation of relief. In the preparation of maps from 
aerial photographs, the cartographer has during stereo- 
scopic examination a good view of the ground relief. 
Contouring from such photographs requires much more 
ground control and much more instrumental work than is 
needed for planimetric mapping. Much though has been 
given to the question of how the relief could be best 
indicated without the expense involved in contouring. 
From trials now in progress, hill shading direct from 
the stereoscopic view of the photographs seems a promis- 
ing method. 
Soil surveys are included in most of the projects 
mentioned above and some reference to this is made in 
the article referred to (1). No new techniques in the 
interpretation of soils are reported but there has been 
a notable increase in soil surveying in the overseas 
territories and both air photographs and maps prepared 
from them are widely used in the course of this work. 
In this type of interpretation, the qualities of elec- 
tronically printed photographs are most important and 
this is equally true of geologic work. 
Photogeological interpretation is carried out by the 
commercial companies and by the Photogeological Section 
of the Directorate of Overseas Surveys. The commercial 
surveys are largely for individual clients and it 1s not 
possible to list the exact areas covered but they include 
projects in Europe, Africa, the Middle East and other 
parts of Asia. The Directorate, during the last four 
years, has carried out photogeological work and field 
checking in Somaliland, Aden, Tanganyika, Nigeria, 
British Borneo and before independence, in Malaya. 
Though not photographic interpretation in the normal 
gense of the term, the interpretation of airborne geo- 
physical investigations is playing an increasingly im- 
portant part in geological studies (1). Though the re- 
sults of these surveys are normally plotted along with 
airphotographs by the air-survey organizations, the act- 
ual interpretation is commonly carried out by the cli- 
ents own specialists, particularly in the case of miner- 
al investigations. 
  
References: Sweden Report: 
Hoppe, G. 1958: Flygbilden som vetenskapligt 
hjalpmedel (The Air Photograph as a Scientific Tool)- 
Svensk Naturvetenskap 1957-1958. Naturvetenskapliga 
forsknings-radets arsbok, 11. 
Hoppe 1959: Om flygbildstolkning vid jordartskartering 
jamte nagra erfarenheter fran jordartskartering 1 
Norra Lappland (About air photo interpretation at soil- 
mapping and some experiences of mapping in Northern 
Lapland)- Geologiska Foreningens Forhandlingar 
pd 81H 2. 1959. 
Tillampad fotogrammetri (Applied Photogrammetry) - 
Teknisk Tidskrift, 88, p 885-916.