WORK PERFORMED 
BETWEEN THE XI AND XII INTERNATIONAL 
CONGRESS OF PHOTOGRAMMETRY 
1) Photogrammetric Flights: 
Various areas of the country were covered according with a preesta- 
blished program. 
Two aisplanes, Beechcraft B-80 Queen Air and Cessna 310P, hand been 
used for this purpose. 
The photographic area covered reached 767.290 sq. km. 
Aerophotograms were obtained by the use of two Wild cameras model 
R.C. 5a., another two ones, model R.C. 9 and a Wild cone (23x23 cm), 
152 mm focal length adapted to the first camera. 
The scale of-the photogram oscilates between 1:5,000 and 1:75,000. 
2) Terrestrial Survey: 
  
The network of lower order survey required to obtain the aerophoto- 
grammetric aid recognized and meassured during this period, is 
structured by 224 points of III order and 277 points of IV order. (Surface: 
267.500) 
In addition, 202 topographical contour lines had been meassured with 
a total development of 11,000 km. 
3) Analytic Aerotriangulation: 
The execution of analytic aerotriangulations was faced by means of an 
electronic stereocomparator Nistri, model TA 3/P. 
The range of interest was covered by 12 aerotriangulations and com- 
prises about 2,000 sq. km. 
Doctor Schut's method was used for the obtainment of the plani- 
altimetric values of transition length points and their corresponding 
adjustment. 
A Burroughs/3500 was required for the electronic processing of Phase 
| and an IBM 360/40 for Phase Il. 
The experience acquired by the MGI in this kind of activities, enabled 
it to elaborate some methods in order to automatize the process, and 
save the inconvenients dued to the identification or meassurement 
mistakes.