The International Archives ofthe Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B4. Beijing 2008 
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Figure 2. Geodetic co-registration check using orthoimage 
superimposition (left: CTX-HRSC; right:CTX-HiR!SE) 
Figure 3. Multiresolution stereo DTMs compared with each 
other over the Athabasca area. Note the TDI array 
(e) which could not be corrected due to image noise. 
However, 18m CTX DTMs make it possible to depict the shape 
of an individual landscape feature such as a medium scale 
impact crater (radius > few hundreds of metres) or the shape of 
valley and streamline islands. 3.5 m resolution HiRISE DTM 
show finescale detail of very flat areas including surface 
roughness features. 70cm HiRISE DTMs provides a measurable 
sub-metre resolution vertical local roughness. This means that