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APPLICATIONS 
Topographic mapping 
As is to be expected, little change was reported in the field of topographic 
mapping. Sweden reports developments in the orthophoto technique for this 
type of mapping and the U.S.A. that the scale of topographic map being used for 
land development purposes is tending to become larger. In the U.K., the 
Ordnance Survey is making greater use of photogrammetric means on extension 
surveys at a scale of 1:1.250 and for smaller areas of revision under the 
continuous revision programme. The proportion of air to ground survey work 
on these extension surveys has doubled within the past 3 years to 40% and 
it is expected that this figure will increase to 75% when the build-up is 
complete. 
Cadastral mapping 
  
The lack of legal acceptance of photogrammetric techniques for original 
property surveys still seems to be one of the major problems faced by many 
countries. The following applications have been cited: in Sweden, photo- 
grammetric methods for the determination of coordinates have been coupled 
with automatic plotting; in Australia, photogrammetric methods are only 
applied in areas where ground survey practices are too difficult or too costly; 
in the U.S.A., limited use is made of analytical techniques and then usually 
in rural areas. 
Large scale mapping 
  
The trend in France is that all large scale mapping for town planning purposes 
is done by orthophotography, with D.T.M.'s being used for engineering purposes 
(motorways, etc.). In South Africa, however, there is still some resistance 
to the use of photogrammetric methods for surveys at scales of 1:1.000 and 
larger e.g. 99% of the damsite surveys and 50% of the road surveys are done 
by ground survey methods. 
in. the U.K., 90% of the surveys for motorway construction were performed by 
photogrammetric means and the trend is that engineering work as such is 
increasing in proportion to the other large scale surveys carried out for 
re-development of city centres, areas previously occupied by low density 
housing, sites for specific projects (hospitals), etc. In Sweden, where 95% 
of the work is done photogrammetrically, the trend is to use scales of 1:400 
to 1:500 for planning and building purposes instead of 1:1.000. Other 
percentages of large scale surveys carried out photogrammetrically are 95% 
in The Netherlands and 99% in the U.S.A. In the latter case, the scales used 
are as large as 1:120.