10N 
Human V 
  
Human Eye 
  
-43- 
( Some Practical Consequences for Photo-Interpretation. 
  
We are now at the stage of summing up the results, to point at practical 
consequences, to draw conclusionse 
First of all, the title was understood to ask for an outline of the 
physiological and psychological aspects, not for a search for practical 
results, with a direct impact on the profession, It is too early for 
results of this kind; this is also the opinion of Chevallier and Guy 
(private comm, 1968). 
Still there are two general results, or even three: 
First, it became more and more clear to the author, that language is a 
key-factor for photo-interpretation. This holds obviously for the 
professional knowledge and teaching, but it is also of essential value to 
talk, write, and draw during the training phase, Moreover, the knowledge 
acquired from lectures and books in a foreign language is not automatically 
transferred to the mother tongue — and vice versa. The author experienced 
this in an interesting way, when the two students discussed lively with 
their countrymen to translate the summary with respect to its meaning. 
Second, teaching and education of photo-interpretation will benefit most of 
this study, if any benefit comes out at all. This was to be expected: 
physiology of the human eye is a given set of fixed properties, the psycho- 
logy of a person functions in & particular and specific personal manner, 
and the performance to execute tasks will not change by reading the paper, 
but by exercising the task, And it is here that teaching and education come 
ino 
Third, a listing of primary and secondary aspects has been given and shaped 
in the form of a matrix. Although the author feels that this structure contains 
an arbitrary selection of properties, it may be useful for others to see the 
overwhelming amount of data together in & diagram, Modifications are easier 
introduced than setting up & new scheme, 
Finally, we will start here with the first modification, an essential one, to 
keep the matrix up to date, 
Physiology was here understood to embrace the measurable basic properties of 
the eye (Boynton (1967) takes it much wider: "Physiological Optics = Visual 
Sciences"); Psychology then contained the non-measurable properties, and we 
considered the "Responses to Visual Tasks" as a mixed group, which comes 
closest to photo-interpretation, Colleagues accepted the distribution of 
the 14 cards with basic properties as in fige 3 and De 
However, the "Neural Chain to the Brain", the "Visual Fatigue" and the 
"Information Flow and Capacity" are almost completely belonging to the 
measurable domain!