The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B4. Beijing 2008 
Figure 7. True position (road boundaries) on Orthophoto 
The standard deviation for accuracy is calculated for the 
observations and accepts or rejects criteria is determinate for 
each of them using statistical methods described in 
documentation. Orthophoto accuracy should only be controlled 
on good visible objects. 
7. CONCLUSION 
Production of spatial data is still in progress, first experiences 
enabled to improve implemented documents and technology 
procedures. Very important part in the cycle of improvement 
lies on the Croatian Geodetic Institute that controls most of the 
geodetic Products and their role is to evaluate the Products and 
its Specification in the same time. It has to be pointed out that 
the Quality Control System according to ISO norms is in 
constant process of development and improvement. From NSDI 
point of view is very important to include into database official 
and approved data passed on quality control in Croatian 
Geodetic Institute. Main reasons in this proposition are users 
and their needs for accurate data. 
REFERENCES 
Republic of Croatia (2007): Law on State Survey and Real 
Property Cadastre, Official Gazette “Narodne novine”, 17/2007, 
pp. 1309-1328. 
Joint venture of “GISDATA” d.o.o., “Trigger” d.o.o. and “Con 
Terra” GmBH (2006): Consulting Services for system design 
and implementation of the SGA GIS databases and design and 
building of Geoportal and development of WWW sales for the 
SGA, Inception Report, State Geodetic Administration of 
Republic of Croatia 2006. 
Remke, A; Wytzisk, A; Buehler, W, Stipic, D. (2005): Study on 
Development of National Spatial Data Infrastructure in Croatia, 
State Geodetic Administration of Republic of Croatia 2005. 
State Geodetic Administration, 2003a, Product Specification 
Topographic Data 1.0, Zagreb, SGA 
Croatian Geodetic Institute, 2004a, Orthophoto Quality 
Elements and Subelements 1.0, Zagreb, CGI 
Croatian Geodetic Institute, 2004b, Quality Control of 
Geographic Information 1.1, Zagreb, CGI 
Croatian Geodetic Institute, 2004c, Sampling Guidelines 1.0, 
Zagreb, CGI