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gulations show, on the average, that the standard error of unit 
weight is about 9 micrometers in planimetry and about 18 micro- 
meters in elevation. 
Application of Photogrammetry to the Earth Surface Representation 
  
The development of photogrammetric mapping in Sweden during the 
period 1968-1971 has been characterized by a wide rationalizing 
of methods and procedures due to the keen competition for mapping 
commissions. This has meant that the number of persons working 
entirely or partly with photogrammetric mapping has not increased 
since 1968. There has rather been a reduction of the photogram- 
metric staff as shown in table 4. 
Table 4. Number of Persons Working with Photogrammetry 
Organization Number of persons 
1968 1969 1970 1971 
State 339 344 359 253 
Communal 87 75 58 53 
Private 227 2321 246 524 
Total 153 740 763 150 
Methods 
The orthophoto-technique will soon be the only technique used 
in the production of photomaps for the official maps. There is 
also an increasing demand from the town planners to get orthopho- 
tomaps instead of ordinary line maps. 
The use of colour film for aerial photography had a break through 
in the late sixties. In 1968 approx. 30 % of all pictures were