where p is the parallax of the top point of the object in Figure
1 and B is the baseline distance between the two exposure
centers of the camera. In the high-resolution imaging
case, the orbit height His great and makes parallax p small.
However, B is great in both cross-track stereo mode and intrack
stereo mode because the pointing angle of 30" (Quick
Bird) to 45" (IKONOS) yields large baselines by different combinations
of fore-, nadir-, and aft-looking strips. The extremely
long focal length f makes a further contribution to a greater Three lenses can be used, one for each cm linear array