442 
To complete the picture for standardization” of object space, 
ong must consider the three remaining parameters that describe 
the, spatial, orientation of: a photograph. These are the three 
angles which define the rotational attitude of the camera in 
space. For consistency these parameters should describe the 
angular position of the camera relative tofithe local vertical 
of the geodetic coordinates of the-airstation position. -Tf 
this is done, simple: transformations can be‘computed to bring 
these angles into the rectangular system selected for the 
"model." In this way, any photograph can be immediately : 
orientated with any other without the need for any intermediate 
parallax measurement and computation. In fact, it 15 possible 
that adjoining photographs from different projects (and times) 
couid be directiy "set;up" (a valuable tool for change detec- 
tion,.etc.)4. The.onlysmedsuremeünt'that-is-necessary is the 
requirement that the operator "define".the relationship be- 
tween the photographic and macrine coordinate systems (interior 
Orientation)... This reauiresituat precise pointings be made 
of the camera's imaged fiducial markers. 
The third area of concern for standardization is.that.one 
which describes the internal characteristics of the camera. 
Fortunately, this falls in the purview of Commission I of 
ISPGRS and is presently being addressed by H. Ziemann of the 
National Research Council of Canada. Hopefully, Dr. Ziemann 
will be successful in establishingia universal system of 
describing the distortion of a photographic lens that can be 
easily adapted by the users of analytical stereoplotters. 
In this suggested "standardization," all of the internal 
computations for servo response are left to the ingenuity of 
the designer of the analytical stereoplotter. On the whole, 
the form for these computations are usually dictated by 
machine design and computer speed. The accuracy, ease of 
operation, flexibility, speed, etc. are all characteristics 
of individual design which can be measured if the input and 
output are standardized. More important, if one is given 
two photographs with six consistent parameters each (along 
with camera characteristics), he can place them in his 
plotter--make precise points on fiducials and proceed to 
directly extract data.