Scirtryck ur Svensk Lantmatcritidskrift nr 3 1964 
453 
The Stability of the Film. Measurements in 
Diapositives Made from the Same Negative 
Anders AIore n, Division of Photogrammetry 
R. Inst, of Technology, Stockholm 
In order to investigate the stability of the film and its variation from 
time to time after the development, the following investigation was 
made. 
One photograph of the Ôland test area was taken by each of the 
three cameras Ag 38, Ag 41 and Ag 196, Two contact diapositives 
were made June 29, 1963 and then from the same negatives another set 
of three diapositives at an interval of about one month. The differen 
ces between the diapositives were measured in a sterecomparator, Wild 
Stk 824, in twentyfive regularly located points. Thus each diapositive 
was compared to one of the diapositives made June 29 which was con 
sidered as given, i. e. used as reference. The adjustment was made 
according to the metod of least squares, using the following parameters: 
microns