e 
In most applications data corresponding to finite focal settings and coordinates of princi- 
pal point are introduced in the calculations, However different procedures are used : First, fol- 
lowing techniques analogue to aerial photogrammetry, the camera is calibrated independently for 
different focal settings, and the data of interior orientation are then introduced as constants into 
further calculations, Secondly, taking care of the fact that the stability and accuracy of resetting 
of the interior orientation has to be doubted, the same photos are used for an independent calibra- 
tion and successive measurement of the object, Thirdly, this being the most thorough approach, 
the data of inner orientation are regarded as variables to be adjusted in the process of analytical 
evaluation of object coordinates, No investigations, however, are found on the necessary accuracy 
of the data of interior orientation, especially with regard to the photo disposition - parallel or 
convergent - and the depth of field of the object. 
Practically all types of analytical solution known from aerial photogrammetry are also 
used in close-range photogrammetry with one difference : The lense distortion is generally intro- 
duced more sophistically, Methods directly analogue to aerial photogrammetry - photos with 
parallel axes, calculation done in the order relative orientation, absolute orientation - are des- 
cribed in[10] ,[13] . The disadvantage of this method is obviously that the accuracy of the coor - 
dinate components - generally Z - in the direction towards the camera standpoint is less than in 
the two other directions [4], [9]. 
The separate calculation of relative orientation offers, however, easy controls on the 
measurements if all measured points are used for this calculation [10]. 
Better accuracies can be expected with convergent photos [9] and also if the number of 
standpoints is increased and thus redundant rays for the resection of object points are obtained 
[11], following e.g. methods of aerial triangulation, Cases in which coordinates of camera posi- 
tions - this is generally true in terrestrial photogrammetry - are known have not much been in- 
vestigated, The difficulty is the definition of the standpoint - materialized by the camera - so that 
it can be measured with the same accuracy as the field of control points, It would, however, be e + 
worthwhile to study this method, This would also improve the methods of camera calibration which 
normally implement the determination of the standpoint by space resection and in which strong 
correlations between camera constant c and distance standpoint/object are found, 
Methods of resection in space and following intersection of object points are used when 
convergent photos of two or more standpoints are taken [9], [11]. A very general approach to 
the problem is given in [6]. 
Statements on precisions actually achieved are still much varying, High accuracies have 
been achieved in the measurement of parabolic antennas [9], [11]. A very interesting study on 
the influence of varying set-up of photography and on the methods for compiling image coordinates 
as well as on different kinds of control point materialization is contained in [1], [8], [9]. Accu- 
racy can be increased by repeated photos from the same standpoint, by repeated measurement 
in the comparator, and by varying designs of control marks [8]. 
Examples for the practical organization in application of short range photogrammetry 
setting-up of standpoints, preparation of the object, illumination can be found in[2], [3],[10],[11]. 
Literature 
[1] Abdel-Aziz, Y.I., Karara, H, M., - Direct linear Transformation from Comparator Coordi- 
nates into Object Space Coordinates in Close-Range Photogrammetry ; Symposium on Close- 
Range Photogrammetry, 1971 Urbana, Illinois, 
[2] Argyris; J,H, - Messung räumlicher Verformungen mittels photogrammetrischer Methoden 
und elektronischer Datenauswertung ; ISD-Bericht Nr, 118, Stuttgart 1972, 
[3] Bóttinger, W.-U. - On Some Aspects of Taking Close-Range Photographs for Photogram- 
metric Evaluation ; Practical Experiences in Photographing the Models of the Cable-net 
Roofs for the Olympiad at Munich, Invited Paper ISP Congress Ottawa 1972, Commission V, - I^ 
[4] Brown, D.C, - Analytical Calibration of Close-Range Cameras ; Symposium on Close- 
Range Photogrammetry, 1971 Urbana, Illinois, 
as De