The Commission's interest in non—passive.sensors for mapping purposes has 
been noted in South Africa and has drawn attention from a number of 
bodies, official as well as commercial and also educational. 
COMMISSION IV. TOPOGRAPHIC & CARTOGRAPHIC APPLICATIONS 
RAPPORTEUR: Mr. K.J. Lester 
Since 1972 considerable progress has been made in completing the various 
mapping series of the Republic of South Africa. 
The demand for maps at a large scale led to the introduction of the 1 : 10 000 
Orthophoto series in 1968. During the period under review more than 
1200 sheets at this scale covering most of the main urban and peri—urban 
areas, have been produced. In the highly industrialised metropolitan areas 
revision is already being undertaken. 
The 1 : 50 000 series now provides full cover for the Republic. This series 
which comprises 1930 sheets was commenced in 1938 and by 1961 only 25 
per cent of the country had been covered. In the fifteen year period to 1976 
the remaining 75 per cent was mapped at this scale. The problems connected 
with revision at this scale are complex and are proving more difficult to solve 
than the original mapping. It is, however, fortunate that the adoption of 
the metric system has come at the same time enabling it to be regarded as a 
revision of contours. lt is anticipated that every sheet will be revised at least 
once every fifteen years, although many will require revision more often, 
possibly five — to ten — year periods. 
The 1 : 250 000 series comprises 71 sheets and only 7 of these remain to be 
published. 
Complete cover for the 1 : 500 000 series which comprises 21 sheets has 
existed since 1951. During 1974 it was decided to recompile the entire 
series using larger scale mapping. Three sheets have already been completed 
and a further ten are in production. 
The private sector has been engaged mainly on mapping for large scale 
engineering surveys. Orthophoto mapping at scales of 1 : 2000 and 1 :5000 
have been extensively used for new rail link routes, pipeline routes and geo— 
logical exploration. Many of these projects have included DTM. Generally 
speaking this type of mapping has been well received by the users. 
COMMISSION V. NON-—TOPOGRAPHIC PHOTOGRAMMETRY 
  
RAPPORTEUR: Professor K.N. Greggor 
The commercial use of terrestrial and close range photogrammetry has be— 
come common in appropriate application areas and quite a number of organ— 
isations are using terrestrial cameras. The following applications can be men— 
tioned: — : 
— Terrestrial measurement (Ref. 1) of mine—dump volumes; cliff faces; 
bridge sites; dump slopes; ore bodies; etc. 
— High accuracy measurement of aircraft for the purpose of manufacturing 
wind tunnel models. Convergent photography with affine, analytical 
restitution was employed. Special problems were the high accuracy and 
severe depth of field requirements. (Refs. 3 & 4). 
— Alignment and calibration of machinery, to within small fractions of a 
millimetre, using analytical photogrammetric principles and geodetic theo— 
dolite as perspective generating devices. (Ref. 4).