LEM E 
  
MEM ERE 
added to this resolution, so that everybody could 
see that the area to be covered by the proposed 
working group is not limited to graphical maps 
nor to D.T.M. alone, which for some cover only 
altimetry. This emendation was adopted. 
After this the meeting discussed the stereo- 
orthophoto mentioned in Resolution 3. 
Some were afraid that the resolution could be 
interpreted as already recommending the applica- 
tion of this technique. Dr. Ternryd thought this 
was a premature worry. In fact, the resolution 
proposed only a study of the problems related 
to the production and use of orthophotos and 
stereo-orthophotos. Consequently, only a study 
was being proposed. Thus the text was main- 
tained in its original form. 
Finally, Dr. Zarzycki proposed that "space im- 
ages" be replaced by "space data" in the Recom- 
mendation. This modification was adopted. 
Friday, July 23, 1976, from 15.45 to 17.15 
Session 10 of Commission IV 
Topic: Conclusions 
Chairman: Mr. G. Ducher (France) 
Invited Paper 
Author: 
Title: 
Dr. W. Brindópke (F.R.G.) 
Grosse Bildmassstabe für gross- 
massstábige Auswertungen und 
Karten /P /V/05 
Dr. Brindópke's presentation was followed by a 
general discussion in the course of which the 
following remarks were made. 
Mr. J. Visser (Netherlands) returned to the graph 
presented by Dr. Brindópke, according to which 
the costs of photogrammetric methods would 
mount up to only 1/3 of the costs of terrestrial 
mapping methods. Would this hold true in the 
F.R.G.? Would it hold true in India where the 
costs of labour are not as high? 
Dr. Brindópke answered that the information in 
the graph was of a very general nature. The prin- 
ciple holds true for urban areas and for the moun- 
tainous areas in Europe. 
Dr. T. Blachut (Canada) said the idea presented 
by Dr. Brindópke would be interesting for Canada 
where labour is costly. He said he was sceptical 
about the use of analytical block adjustment and 
the use of mono-comparators, due to uncertain 
interpretation. On the contrary, he thought the 
analytical plotters make it possible to improve 
both accuracy and speed. 
Dr. Brindópke, again, thought that analytical plot- 
ting could be carried out in two ways: analytical 
plotters for the linear details and natural points; 
mono-comparators for targeted or artificial points 
offer no difficulty of interpretation. 
Dr. B. Dubuisson (France) spoke of parameters, 
saying they included the choice of the number 
of stereo-pairs and the number of points per 
stereo-pair. 
Dr. Blachut said the experience gained in Canada 
tends not to recommend the use of mono-com- 
parators. 
Dr. B. Makarovic (Netherlands) said that, to judge 
from the experience gained from mono-photo- 
grammetry at the I.T.C., it was necessary not only 
to target in advance but also to measure the 
114 
NA A E EE 
height of the buildings. A good number of ques- 
tions still need to be answered. 
Mr. H. Desportes (France) observed that, when 
using very large scales, buildings tend to hide 
important details due to perspective. 
Panel Discussion 
Topic: Conclusions 
Moderator: Dr. B. Dubuisson (France) 
Panelists: Dr. U. van Twembeke (Belgium) 
Dr. T. Blachut (Canada) 
Mr. M. Thompson (U.S.A.) 
Dr. G. Birardi (Italy) 
A panel moderated by Dr. Dubuisson then dis- 
cussed conclusions arising from Commission 
IV's proceedings at the Congress. 
Mr. Thompson presented a number of conclusions 
concerning automation in photogrammetry: 
— it is possible, at a relatively low cost, to equip 
plotters with recording apparatuses or minicom- 
puters and to thus automate the processes 
— analytical systems, being much more sophis- 
ticated, make it possible to go further, but they 
require considerable investments 
— systems of differential orthoprojection make 
possible a reduction of costs 
— satellite imagery, again, provides synoptical 
data that can be automatically processed, and 
analyzed so as to extract thematical information. 
It is not to be forgotten that the use of automa- 
tion is costly and that any success demands 
patient and untiring effort. 
Dr. Birardi remarked that satellites actually pro- 
vide data of use especially for revision purposes 
— under certain circumstances even at medium 
scales. Consequently, it is important to obtain 
photographies at shorter intervals, perhaps with 
the help of fixed orbits. Anyway, it can be hoped 
that spatial imagery will provide a solution for 
problems of revision. 
Dr. Blachut said the worldwide need for carto- 
graphic services was enormous, as compared 
with what is already available, and, above all, 
as compared with the necessity of evolution in 
the areas of demography and economics and the 
necessity of an inventory of our own resources 
that we know so little about. Meanwhile, we 
should be working at a plan for the use of these 
resources. Classical maps and orthophotomaps 
(including stereo-ortho) have to be produced as 
quickly as possible for purposes of land use, 
an end that passes by far those of cadastre alone. 
Dr. van Twembeke said he would like to make 
two series of remarks concerning multipurpose 
maps: it is important to be cautious with digital 
data that are not directly apprehensible, but have 
to be graphically converted. On the other hand, 
the difficulties in producing multipurpose maps 
are more of a psychological nature than a tech- 
nical one, as far as the dialogue and consulta- 
tions with users are concerned. 
Dr. Dubuisson said a concluding word about the 
necessity of geographical localization to enable 
a correlation with socio-economic data banks. 
Two principles are to be taken as a basis for 
such data banks: 
— frequent output justifies their use 
— various data banks are to be connected with 
each other by so-called "gangways".