CHOICE OF STATION AND CONTROL FOR EFFICIENT ORIENTATION
AND PLOTTING IN ARCHITECTURAL PHOTOGRAMMETRY
In architectural photogrammetry the necessity of photographic coverage of
buildings under conditions of close quarters and city traffic requires a choice of
camera stations which, in their relation to the subject to be plotted, are quite unlike
those in aerial photogrammetry or other terrestrial photogrammetry.
Short bases of stereopairs, great depth of plotting and inclination of the cam-
era axes to the vertical and to the normal of surfaces to be plotted invalidate the
assumptions that allow one to isolate the elements of relative orientation in the nor-
mal orientation procedure of aerial photogrammetry.
From among many camera positions which have been used in the author's
projects in architectural photogrammetry this report describes photography on the
diagonal to two elevations of buildings, a system which has been repeated through
necessity and through choice. Survey control is provided by measurements on the
buildings themselves. The orientation procedure in the A 7 Autograph is a combi-
nation of relative and absolute orientation with particular concern for eliminating |
error of convergence of the camera axes. Plotting is in both plan and elevation, using
aerial and terrestrial gear systems of the A 7 Autograph. The resulting plottings,
though requiring the rotation of foreshortened elevations into full frontal projection,
provide the best determination of inaccessible dimensions on the buildings, necessary
for control of plotting of more nearly frontal stereopairs.