Fig. 6From: Optical satellite sensor and positioning accuracy analysis for the Hongqi-1-H9 wide-range satellite in different terrainsGeometric positioning error bar graphs when using five GCPs. The black crosses represent the point positions in the World Geodetic System 1984, and the blue and red arrows indicate the plane and elevation errors, respectively. a–c show the results for the urban, plain, and mountainous areas, respectivelyBack to article page