High Resolution Stereoscopic (HRS) SPOT5 images with resolution of 2.5 m can be used to produce image maps in large scale. The main problem in this process is the geometric correction, especially in the case of area characterized by rough ground (sharp relief). The orthorectification is an important process and has to be done for the purpose of producing image maps. There are different models can be used for performing the orthorectification process such as physical and polynomial models. The differences between physical mathematical model of orthorectification and that of different polynomial models named as first order, second order, third order, fourth order and fifth order polynomials have been discussed practically in this research. The Result images corrected by the different methods are checked carefully. The results of applying the physical model and third, fourth and fifth orders polynomial were approximately the same. Increasing the number of GCPs in the fourth and fifth polynomial orders did not improve the accuracy of results. Orthorectification is the only way to meet the expectant accuracy of 1:50000 image maps.
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