A foliage-penetrating radar altimeter was developed by the Radio and Electrical Engineering Divısıon of the 
National Research Council at the request of the Canadian Forestry Service for Scale determination in low altitude 
photography. Versions of it are in use by several organizations (11, 12); the current manufacturer being G. T. W. 
Resource Inventory Radar Limited. 
The Canadian Centre for Remote Sensing use a special closed circuit T. V. in their CF 100 to provide 
downward visibility. Conventional navigation aids in their aircraft are as follows: 
CF 100: R Theta computer Dakotas: Tacan and ADF 
Tacan 
Radar Altimeter 
Falcon: Collins VHF VOR/IES 51RVI (Dual) Collins Weather Radar WP-103G 
Collins ADF Receivers DF 203 (Dual) Collins Primary Flight Director System FD-109H 
Collins Market Beacon Receiver 51Z4 Collins Secondary Flight Director System FD-109F 
Sperry Primary Compass System C-11 Collins Flight Control System AP104 
Sperry Secondary Compass System C-9 Stewart Warner Hi Range Radio Altimeter S PN-159 
RCA DME AVQ-T5 GPL Doppler Navigation System GPK-1000/GPO-601 
Bendix ATC Transponder TRA61Z IDC Encoding Altimeter 
Altitude Reminder 
Recording Materials 
For photogrammetry Kodak 2405 Double-X remains the common film with some use of 2403 Tri-X, 
For photo interpretation, especially research aspects, the use of colour is increasing greatly (13-16). 
In 24 cm width the chief film is Kodak 2445 colour negative with 2443 false colour reversal second, 70 mm 
colour films in order of usage are Kodak 2443 false colour reversal, 2448 colour reversal and 2445 colour 
negative, Black and white films still accounting for 2/3 of the 70 mm and 1/3 of the 24 cm are 5063 Tri-X 
2424 Infrared, 2405 Double-X and 8401 Plus-X. 
Other recording materials are magnetic tape and chart paper. Both are used with the various sensors 
of the Canada Centre for Remote Sensing. Terra Surveys uses magnetic tape. 
Processing 
The use of continuous processing machines for film and paper has increased with the introduction of 
several models of the Kodak Versamat and one Pakomatic. 
The Ministry of Energy, Mines and Resources, NAPL Reproduction Centre (formerly Air Photo Production 
Unit) has undergone major expansion to support the Canadian Centre for Remote Sensing as well as its traditional 
survey role, 
A source for sensitometers of aerial films has been defined from 350 nm to 920 nm and it is incorporated 
in processing control sensitometers (17). 
Image Location 
Considerable research on measurement causes and correction of image location errors has been done 
(18-32) mostly in the Photogrammetric Research Section of the National Research Council. They organized 
a conference on the subject in 1970, 
Image Quality 
Several studies have been made of resolution in black and white and colour materials and the implications 
for practical situations (33-39). 
Space Photography 
The Canadian Centre for Remote Sensing is responsible for acquisition, reproduction and distribution of 
ERTS data of Canadian territory. To this end, comprehensive data reduction facilities are being established 
in Ottawa and it is anticipated they will be ready to handle data from ERTS "A" whose current launch date is 
July 21st or July 24th, 1972. 
Studies on lunar orbiter photography have been carried out at the University of New Brunswick (40). 
Underwater Photography 
Laval University have made use of underwater photography (41).