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1:25.000 SCALED PHOTOGRAMMETRIC MAP PRODUCTION SYSTEM 
O. Firat*, K.Pamukoglu, O. Eker, Ô. T. Ôzerbil, H. H. Mara? 
General Command of Mapping, Photogrammetry Department, Dikimevi Ankara, Türkiye - 
(orhan.firat, kadri.pamukoglu, oktay.eker, tuncer.ozerbil, hakan.maras)@hgk.mil.tr 
KEY WORDS: Photogrammetry, DEM, Orthophoto, Production System, Automatic Feature Extraction 
ABSTRACT: 
By applying the latest developments occurring in photogrammetry to the map production systems, important reductions in map 
production costs are obtained. For instance, by starting to use digital cameras and GPS/IMU systems in taking aerial photographs and 
in aerial triangulation, there is an opportunity of reducing the number of ground control points that must be established due to map 
production, film costs, photo-laboratory costs and the scanning costs which are done at sensitive scanners. Whichever way the 
development of the map production procedure is aimed, by integrating the new scientific and technological developments in 
photogrammetry, especially in automatic feature extraction, into map production systems, the photogrammetric feature extraction 
process duration, which is one of the biggest components of map production cost, will be reduced. The operator effect will be lower 
and finally the costs will be reduced. In this paper, firstly, the photogrammetric feature extraction steps used in the present 1:25.000 
scaled map production process in General Command of Mapping are examined and the production duration and costs are investigated. 
In the current production system, feature extraction is done by the operators from stereo models which were created by using aerial 
photographs. Extracted features are examined by the operators again for the cartographic and topologie rules and then the corrections 
required are done. Thus the photogrammetric production is completed. Secondly, a new alternative system is introduced to reduce the 
production duration, operator effect and the costs. In the alternative system, a DEM (Digital Elevation Model) is produced from the 
1:25.000 scaled DECM (Digital Elevation Contour Map) of that map. These DEMs are edited on the 3D models and the corrections 
are made, streams are extracted and added into the DEM as breaklines. By using these DEMs, ortho-images with 1 m spatial 
resolution are produced from the aerial photographs. Also, the contours of the map are generated automatically with 10 m interval by 
using the same DEMs and these contours are edited on stereo models and thus auxiliary contours are added. By using the semi 
automatic data extraction software, firstly, features that can be extracted from the ortho-images (roads, lakes, etc.) are extracted. 
Remaining point features and the line features that cannot be extracted automatically (small paths, fences, etc.) are extracted 
manually by the operators. Finally all data extracted automatically, semi-automatically and manually are combined and checked and 
the photogrammetric production steps are completed. In the latter part of this paper, the problems faced and the subsequent solutions, 
while applying the new alternative system, are introduced. Finally, both systems are compared to each other according to the 
accuracy, production duration and cost. 
1. INTRODUCTION 
In recent years, technology has become cheaper and more 
widespread and developed, and this has made it possible in 
photogrammetry to reduce the map production costs. Using 
digital cameras and GPS/IMU systems in taking aerial 
photographs and in aerial triangulation, there is an opportunity 
of reducing the number of ground control points that must be 
established due to map production, film costs, photo-laboratory 
costs and the scanning costs which are done at sensitive 
scanners. 
On the other hand, photogrammetric feature extraction is one of 
the biggest components of the map production process in the 
sense of time spent and costs. Minimizing this step and the 
operator effects in map the production process affects the costs 
directly in a positive way. That is why it is essential to integrate 
automatic feature extraction developments into the map 
production systems. 
In the second part of this study, the methodology and 
photogrammetric feature extraction steps applied in present 
1:25.000 scaled map production process in General Command 
of Mapping are investigated and the time spent and costs are 
scrutinized. 
In the third part of the study, a new alternative system is 
proposed to reduce the production duration, operator effect and 
the costs. By introducing the alternative system, it is aimed to 
integrate a semi-automatic feature extraction software to the 
map production process. In the final part of the study, the 
problems faced when using the alternative system, and the 
reasons for them, are taken up. Both systems are compared to 
each other regarding the production duration and costs. 
2. PRESENT WORKFLOW OF 1:25.000 SCALE 
PHOTOGRAMMETRIC MAP PRODUCTION 
In the present work of 1:25.000 scaled photogrammetric map 
productions (revision of old maps), 1:35.000 scaled black and 
white aerial photographs are used in General Command of 
Mapping. The aerial photographs are digitized by scanning in 
the precision of 20-21 microns. Aerial triangulation is carried 
out by kinematic GPS and outer orientation parameters of each 
photograph are determined by bundle block adjustment. 
In the present work, all topographic features except contour 
lines are extracted by the operators three dimensionally from the 
stereo models which are created by using the outer orientation 
parameters of each photograph. 
Contour lines are imported from the DECM that is created for 
the whole country once, and verified by overlapping on the 
stereo models. The contour lines which are different and 
incorrect according to the stereo model are corrected by editing 
or deleting and reprocessing. Photogrammetric production is