5. ORGANISING ASPECTS
5.1 Hardware aspects
At present, one high-performance digital-photogrammetric
workstation is available (DPW-770) and twelve analytical
instruments. The analytical instruments are intensively used for
mapping now, and not written of yet.
This year, our workstation will be used for development of new
products mainly. In a successive stage, this instrument will be
used for new products like orthophotos. Gradually digital
workstations will substitute analytical instruments for mapping
purposes too, assuming that problems dealing with data storage
and processing speed are solved.
The DCCS-system is still used for semi-automatic aero-
triangulation, although this system is written-off already.
If our tests of the module for automatic aerotriangulation are
successful, a stripped version of the DPW-770 will possibly be
used for aerotriangulation.
Mapping with lower accuracy can be carried out efficiently on
relatively cheap pc-systems, like our DVP. A test on vegetation
mapping with the DVP will be executed in the near future.
Most likely, positive test results will lead to an operational use
of pc-systems for (vegetation) mapping afterwards. Up to then,
the existing process, using stereoscopes, will be continued.
5.2 Personal consequences
Essentially the use of digital photogrammetry doesn't decrease
the annual demand for human-power in our production unit.
The expected efficiency increase, for example with automatic
aerotriangulation, will at least be compensated if not out-
weighed by extra human-power needed for making new
products. Growth of human-power is expected to be about three
human-power years annually.
A change in workflow must be taken into account. Besides an
extra stage needed for scanning photographs, new operations
like correcting automatically generated DEM's arise. These
operations need a change in mind for the operators working
with the new techniques.
Digital photogrammetry makes use of new hardware
components, such as stereo screens, that may be more tiring for
operators.
People working with analytical photogrammetry now, need
additional training for using digital photogrammetry. A sub-
division is made for three types of training:
l. a basic training on digital photogrammetry in general,
containing subjects like contents and structures of digital
images, matching, orthophoto generation et cetera.
This training is meant for all operators working with digital
photogrammetry;
2. atraining for operators on specific digital-photogrammetric
instruments;
3. an advanced training for a small group of users. These users
are skilled to solve particular problems dealing with the use
of digital photogrammetry, for example matching problems.
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6. CONCLUSIONS AND OUTLOOK
In this paper our approach to digital photogrammetry is
described, focused on our experiences in the past and present.
Up to now we use the DCCS for semi-automatic aero-
triangulation. Furthermore, we have purchased a pc-system for
mapping, and a workstation for research and product
development and one for product development and production.
Digital photogrammetry delivers us the opportunity to speed up
aerotriangulation, to do lower accurate mapping with cheap
systems, and to generate new products (high dense DEM's,
orthophotos and bird's-eye-views). The last mentioned gives us
the chance to wide-out our spectrum of products. The new
products are primarily used for integral databases for coast and
river management.
Finally, the use of digital photogrammetry answers the MD's
objective to be one of the front liners in the Netherlands in
using new techniques.
For the next few years we expect digital photogrammetry to be
developing into a technique giving us the advantages mentioned
above. In a later stage, digital-photogrammetric workstations
can most likely substitute analytical instruments for mapping.
7. REFERENCES
. Ackermann, F., 1991. Structural Changes in Photogrammetry.
43" Photogrammetric week, Stuttgart
. Dowman, LJ., 1993. Developments in digital photogrammetry:
revolution, evolution or extinction. NGT Geodesia 93-8, pp.
367-371
. Gunst, ME. de, J.E. Den Hartog, 1994. Knowledge-Based up-
dating of Maps by Interpretation of Aerial Images. 12"
Conference on Pattern Recognition, Jerusalem, Israel, October 9-
13, 1994
. Han, C.S., 1992. Digital Photogrammetry at the Survey
Department. ISPRS, Comm. II, pp. 297-302
. Huising, E.J., E.M.J. Vaessen, 1996. Laser scanning and air-
borne video for management of the sandy coastal zone of The
Netherlands. Proceedings of "3c Nederlands
Aardwetenschappelijk Congres', Veldhoven, The Netherlands,
May 2-3 1996
. Kloosterman, E.H, L.M.L. Zonneveld, J.A.M. Janssen,
C.E. Beers, R.W.L. Jordans, 1995. Vegetation mapping and
monitoring on different scale levels on the island of Ameland:
Methodology and preliminary results. BCRS report 93-24, ISBN
90 5411 100 3
. Tang, L, C. Heipke, 1996. Automatic Relative Orientation of
Aerial Images. PE&RS, Vol. 62, No. 1, January 1996, pp. 47-55
. Trinder, J., B. Donnelly, 1996. Digital Photogrammetry, What It
Can Do and How It Will Affect the Future of Photogrammetry.
Geodetical Info Magazine (GIM), January 1996, pp. 6-8
. Welch, R., 1992. Photogrammetry in transition - Analytical to
Digital. Geodetical Info Magazine (GIM), July 1992, pp. 39-41
. Wicherson, R.J., 1994. Vergelijking digitaal- en analytisch-
fotogrammetrische hoogtebepaling ten behoeve van strand-
profielmetingen. Internal MD-report, MD-GAR-9420 (in Dutch)
. Wicherson, R.J., J.G. Van der Kraan 1995. Het gebruik van
Remote Sensing opnamen en kleinschalige luchtfoto's bij het
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