have been installed in two newly equipped rooms, with 
filtered air and new electrical and computer cabling 
(Figure 3). These make an impressive sight and have 
attracted a stream of international visitors. Presentations 
by OSI staff have generated great interest too, adding to 
the high morale. 
5.0 CONCLUSIONS 
With two scanners and 15 DPWs, OSI is probably the 
foremost organisation in the world in the use of digital 
photogrammetry, with the exception of DMA. The new 
technology, however, is underlain by more subtle factors 
in the success, such as: extensive training by an 
experienced instructor; integration of the system with 
OST’s existing systems and procedures, for example very 
fast set ups of the DPWSs using plate coordinates from the 
DSR1 in conjunction with ground coordinates from 
PAT-MR; colour stereo superimposition, meaning that 
any of the 15 DPWs is suitable for deployment on feature 
collection for database revision, so that OSI will derive 
considerable benefits in the future in its continuous 
updating programme; and careful attention to system 
management combined with the flexibility to change in 
the light of experience. Though feature collection will 
only become more attractive on the digital workstations 
as automated tools become available, a modern national 
mapping organisation must undoubtedly have DTMs and 
orthophotos on its product palette. 
It has been fortunate that national funding was available 
at the time when radical solutions to OSI’s customers’ 
demands were urgently required. OSI has been equal to 
the challenge and responsibility of such major 
investments, but it continues to learn that the successful 
application of digital photogrammetry owes as much to 
dedication and experience as technology. The 
installation of such a large system in several phases, the 
connection to existing systems in terms both of computer 
networking and flows of image, control, DTM and vector 
data, the training of staff in both procedures and 
workflows, and the continuing upgrading of hardware 
and software in situ have been challenging tasks. It is 
almost three years since the first system was installed 
and useful experience has accrued. Production targets are 
being met and not only is digital photogrammetry 
essential for the DTM and orthophoto work but it 
performs very well for map compilation too. 
ACKNOWLEDGEMENTS 
The authors are grateful to a number of colleagues, in 
both Dublin and San Diego, for providing material used 
in the preparation of this paper. 
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