make-shift lab but, in this instance, the shipyard's 
regular photographic lab was made available. However, 
the photogrammetrist provided his own processing equipment. 
Figures 7 and S are typical photographs obtained with 
the photogrammetric camera shown in Figure 6. The camera 
is specially built for survey work and is characterized 
by its distortion-free lens and use of glass plates rather 
than ordinary film for dimensional stability of the 
recorded scene. At mid-1978 this camera would cost about 
$20,000 with basic accessories. 
Plate Preparation and Mensuration 
While at the job-site a sketch was prepared showing 
the approximate locations of all targets. Later on 
each target was assigned a unique number so that a target 
image would always have the same identification number 
on all photographs on which it was seen and measured. 
Once the photographic plates were received at the photo- 
grammetric laboratory the image of each target was located 
under low power magnification, circled. in ink on the glass 
side of the plate and identified according to this 
previously adopted numbering scheme. The target sketch 
served as a guide for this plate preparation work and, 
in turn, the annotation on the plates along with the 
Sketch served as guide for the operator of the measuring 
engine. 
Measurement of the plates was performed on the Kern 
MK2 monocomparator shown in Figure 9. The measurements 
(in essence the XxX; of Figure 1) are obtained 
ij* Yi] 
simply by moving a stage, upon which a photographic plate 
rests, beneath a fixed optical viewing system such that 
-16=