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The PERCEPTION OF SPACE in its general sense is rather an essential 
factor in day-to-day life — but it does not play the same role in photo- 
interpretation and photogrammetry. Vernon means with "space" the 
three-dimensionality of objects and background, the space we live in, 
  
and which we learn to interpret (Vernon 1962 Ch. 8). Horizontal and 
yertical orientation, depth and distance perception have to be trained 
for years. Vernon's final alinea is of value for more perceptual acts: 
"Thus the normal adult can extend and interpret his immediate percep- | 
tions of space by means of ideas and images which become integrated with 
his perception. These he commonly uses without being aware of their 
Value, 0.2.4000. " (Vernon 1962, p.13T). 
PERCEPTION of MOVEMENT is of great significance to us, 
since any moving object may be potentially dangerous; 
N indeed infants react, almost as soon as they are born, 
  
— on moving objects (Vernon Ch. 9). 
E of movement; memory is more essential to 
   
Involuntary eye-movements have & bearing to ihe 
Space perception. 
[In photogrammetry, movement of the image relative to the MM occurs 
during plotting and when operating an ortho-projectos; very harmless 
jobs indeed. The author cannot think of any practical consequence; 
but considers the next experiment, which relates movement and space, 
interesting enough for the physiology of vision, to be cited here, 
Viewing & linearly moving pendulum with one eye through a dark glass 
filter and the other eye seeing directly gives the impression that 
ihe pendulum swings through an elliptical orbit. Thus movement, if 
presented darker to one eye, is probably retarded &t the retina, and 
can give time lag which, after correlation, gives the impression of 
depth, a spacial phenomenon.] 0 3 
PERCEPTION of SHAPE and PATTERNS is one of the most 
essential perceptual activities for photo-interpretation, 
and comes probable before stereoscopic height perception 
and surely before colour too. 
Some shape and pattern perception is without knowing 
the names of the objects and their classification, as 
proven by experiments with operators who suffer from 
  
brain dammage and cannot form the link between seeing 
and the language centre of the brain (Sperry 1964 and Gazzani ga 1967). 
However, as a whole perception functions in terms of language. This 
probably does not go so far that infants cannot see the difference 
between a large and a small square if they do not yet know the words for 
large and small, but the difference between a hexagon and a pentagon 
needs counting, thus words, to be perceived.