l COMMISSION II Instruments for data reduction 
In Sweden the 1960's were a period of pronounced photo- 
grammetric activity and expansion. The major part of the 
instrumentation that now is in production was procured 
during that decade. During the period 1972-1915 the number 
of photogrammetric instruments in use has been fairly 
constant. The number of automatic coordinate printers 
however has increased considerably (by almost 50 %). 
Table 5 shows the number of instruments of different types 
used for production and for educational purposes. 
  
  
  
  
  
  
  
  
Table 5 
Type of instrument | Humber i 
1972 | 1973 | 1974 | 1975 | 
| tereo conparater 3 3 3 4 | 
m A 1 1 1 1 
AS 1 2 2 | à i 
" 46 5 6 5 3: 
" A7 10 10 10 10 i 
" A8 50 51 52 | 9 ' 
" — A9 3 3 2 nnns] 
" A10 2 2 PRESE. 
"E 15 16 16.1. 16. | 
" 59 3 3 3 | 3 1 
Stereoplanigraph 2 2 2 2 ond 
Stereometrograph 8 8 8 8 | 
Stereosinplex II 1 \ 1 2 1 | 
« III 4 4 & 4 
Topokart 1 1 1 1 
lsh 1 1 1 1 
plex 45. 147 45 44 
ultiplex 21 | 22 22 22 
Co-ordinate printers 20 | 20 24 29 
Orthoprojeotors 2 2 2 2 
p 8 | 8 8 
  
  
  
During the period interest has to a great extent been 
concentrated on analytical and digital methods. Computer 
programmes have been developed for digital registrations 
at the stereoplotter for automatic drawing on flatbed 
plotters. Increased use has been made of small desk 
computers in map production. Thus numerical methods are 
often used for the relative and absolute orientation of 
the stereomodels.