REVISION DES CARTES 
COMMENT WITH RESPECT TO " MAP REVISION " 
M.H. MACLEOD 
Carl Zeiss Canada 
In considering "map revision" generally we do so with certain pre-conditioned ideas in 
mind: - 
1. that the "map" is a graphical two-dimensional piece of paper with ink to represent topographi- 
cal features ; 
2. that the "old map" is becoming out-dated due to changes on the ground - the old map requiring 
up-dating at that scale in order to retain it's usefullness ; 
3. that the "map revision' process involves one of the following : 
, a) that of eracing out-dated topographical detail from the "old" map and adding the new detail, 
e 
b) that of introducing partially or totally a new and perhaps different map product or overlays 
to a map product. For example, certain features out-date faster than others,e. g. urban sprawl, 
etc., and hence this overlap can be replaced by an orthophoto overlay - the other overlays, e.g. 
contours, etc., being overprinted into the new map ; 
or 
— > 
c) that of introducing completely automated techniques usually involving computer scanning hardware ; 
or 
d) that of introducing semi-automated techniques (definition and explanation to follow). 
Clearly, the "best" technique for any one country or agency to adopt is based upon, 
past practises, 
present methods, 
and future projections 
and is strongly influenced by local, 
hardware, 
software, 
and human experiences. 
Thus a 3 x 3 matrix with definite and strong correlation between elements : 
  
Past Present Future 
Hardware T. 1.2 1,3 
Software 2.1 2.2 2.3 
Humans 3.1 3.2 2.2 
* * 
* 
To comment upon each of the above points from a ''semi-automated mapping' point-of-view. 
  
Definition - Semi-automated mapping being defined as a system whereby in getting from the terrain 
to the final map, the data passes through a digital state. The digitizing is performed directly in the 
stereoplotting instrument by the stereo operator. The system uses inherent capabilities of the stereo 
operator as utilized in conventional stereoplotting procedures ; identification, interpretation, inter- 
polation, extrapolation, integration and codification. 
An essential feature of the semi-automated mapping system being that the stereo operator 
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