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INTRODUCTION 
Amongst the many resolutions passed at the XIV Congress of the International 
Society for Photogrammetry and Remote Sensing held at Hamburg, Germany in 
1980 was Resolution T.V/3 "Offshore and Industrial Photogrammetry". 
Resolution T.V/3 reads as follows : 
"The Congress, noting the increasing demand for the use of 
photogrammetry offshore, for engineering metrology, realising 
that certain shortcomings may exist in other methods used in 
engineering metrology, recognising the importance of developing 
sources of energy in a hostile environment, recommends that a 
working group be established to develop the potential of coastal, 
offshore and underwater photogrammetry for engineering metrology 
and to explore promising avenues of application in industry". 
Most aspects of coastal and offshore photogrammetry, although interesting 
from the point of view of developing special techniques, do not pose quite 
the same problems and difficulties experienced in underwater photogrammetry. 
Two major problems are met in the application of underwater photogrammetry 
in engineering metrology. These are 
1. Availability of suitable cameras 
2. Underwater manoeuverability and illumination 
The Department of Surveying of the University of Cape Town has been under- 
taking research in underwater photogrammetry and is presently developing 
techniques for the application of underwater photography in coastal 
engineering metrology. 
SCOPE OF THE RESEARCH PROJECT 
The requirement of the project is to provide expertise and help towards 
establishing an operational underwater close range photogrammetric ability 
within a sponsoring scientific/engineering institute. In a multidisciplinary, 
budget conscious, scientific institute, the great difficulty in persuading 
the appropriate authorities to expend large sums of money on highly 
sophisticated mapping and analytical stereophotogrammetric equipment and 
metric cameras is well known and any research towards the use of such 
sophisticated laboratory equipment can be considered as being an interesting 
academic exercise but with limited possibilities of being adopted in the 
field of engineering metrology. Schwidefsky (1970) defined the term 
precision photogrammetry as being when the relative mean square error of the 
distances from the camera lies between 1/1000th and 1/10 000th of the 
distances. With this definition of precision in mind tests were undertaken 
underwater and on the surface using NIKONOS III underwater cameras to 
establish the potential accuracy of the camera systems. 
  
On the premise that the sponsoring Institute would not contemplate the 
purchase of precise photogrammetric comparator equipment to measure the 
photographic image, the possibility of using a presently available mini- 
computer graphic system equipped with a digitiser tablet and to be used in a 
comparator mode is being investigated. 
Finally photogrammetric techniques are being developed and suggestions made 
towards setting up an operational close range photogrammetric ability within 
the particular Institute. 
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