CONCLUSIONS 
As a result, when deriving the D.T.M 
from the same survey as that to be orthophotoprinted, enlarge- 
ments of up to 4.5 or 5.0 times are allowed for the orthophoto, 
while complying with well established map accuracy standards, 
(see table 2). 
Conversely, each time a D.T.M from a scale smaller than that of 
the survey to rectify is available, it is strongly recommended 
to use this one, since it could be more cost-saving. Examples 
are given showing that a D.T.M derived from a scale smaller than 
that of the survey to rectify by a factor of 2, 3 or 4 times, 
allows enlargements of as much as resp. 3.5 times, 3.0 or 2.3 
times for the orthophoto,(see'example of Individual form andtables). 
Existing height databases and/or D.T.M derived from space surveys 
should therefore be taken into account whenever possible, when 
off-line differentially rectifying a given survey. 
The scale of the photograph to be rectified is the driving 
factor. : 
The scale of the DTM, namely that of the aerial photograph 
from which the D.T.M. is derived, has the least impact on 
the results. 
Fully digital processing methods, which should still improve 
the end-product quality, will be an incentive for further deve- 
loping the stereo-orthophoto technique. Appropriate tests at 
scales smaller and larger than those used in the present OEEPE 
test, could be conducted later on, in order to assess the actual 
possibilities evolving from CCD cameras and digital rectification. 
The results obtained in this OEEPE test apply to whatever kind 
of data is used in input, in analog or digital format, either 
from field, aerial or space survey; these results are indepen- 
dant of the technology used in production, whatever type of 
off-line orthophoto-printer is used,optical or digital. 
  
  
APPENDICES 
REFERENCES 
JOURNALS: 
~ ALI, J.and I.J. DOWMAN, oct 1988 : Map revision from [4] P. DENIS and G. GUILLOUET : Restitution photogrammétrique 
stereo-orthophotographs -"Photogrammetric Record’, de couples SPOT (1 exemple d Aix-Marseille) -"Bulletin 
12 (72) pp 847-856. d'information de l'IGN'n° 56 (déc. 1988) - pp 10-18. 
BOOKS: 
-  DUCHER, G. May 1991 : OEEPE test on orthophoto and stereo-orthophoto accuracy. — OEEPE Official Publication N° 25. 
GREY LITERATURE: 
[1]Dr.. SANDOR BALLA : The construction of base-maps from 
: ; À ; : - — Dr. K. KRAUS,1978 : Digitally controlled production of 
[,j M elltte 1mages. : Making topographic map by analogue orthos and stereo-orthos. Com IV,ISPRS*Photog. Eng. and 
; ; and digital methods using soviet satel- Remote Sensing"- vol 45 - n? 10 - oct. 1979. 
lite images. Paper delivered at the ICA 14th Conference 
Budapest (August 1989). 13|6. TOGLIATTI and A. MORIONDO : Evaluation of the accuracy 
— DUCHER, G. Jul 1980 : Essai de stéréo-orthophotographie of the metric camera images for the production of line 
à l'IGN et perspectives spatiales. maps and orthophotos. Metric Camera Workshop (Feb.1985) 
Presented paper to the 14th ISPRS Congress at Hambourg ESA - SP-209 Proceedings pp 29-34. 
1980. WG IV/5. 
LIST OF OPERATIVE CENTERS 
  
{ ACRONYMS NAMES ACRONYMS NAMES 
  
  
ITC (NL) International Institut for Aerial Survev and 
GID (DK) Geodaetic Institut of Denmark-Copenhaguen (Denmark) Earth Science-Enschede (The Netherlands) 
IFAG (D) Institut für angewandte Geodäsie (Federal Republic 
of Germany) ITPT €1) Istituto di Topografia ael Politecnico 
Torino (Italy) 
IGM (I) Istituto geografico militare - Firenze (Italy) NBS (SF) National Board of Survey - Helsinki (Finland ) 
IGN (F) Institut géographique national - Paris (France) NLS (S) National Land Survey - Gävle (Sweden) 
IPTU (A) Institut für Photogrammetrie, der Technischen 
: Den 15 S N N Natione sea = il - ë 
D M Re MastaV en (Austria) NRC (CDN) | National Research Council Ottawa (Canada) 
: ; UC Ini jtv ; 2 
IPUS (D) Institut für Photogrammetrie der Universität et (cm University college Lotion (UK) 
Stuttgart (F.R. Germany) 
  
  
  
WH (CH) Wild-Heerbrugg Company (Switzerland) 
  
  
  
  
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