There are good reasons to believe (from other 
tests we produced with 53 and 60 degree incidence 
angle images) that the same methodology if applied 
on shallower stereo geometry and also at large 
incidence angles would have been more reliable due 
to an increase in correlation success for the 
entire image. The relative impact on overall 
precision of scene detail and viewing geometry has 
yet to be determined. We believe that more tests 
with multi-incidence angle SIR-B images are still 
required for a better understanding of this 
relationship. Also, the actual method for 
measuring parallax between stereo pairs would have 
to be refined in order to effectively lead the 
search process to a reliable and precise 
function. 
ACKNOWLEDGEMENTS 
The authors are very grateful to Dr. M. Kobrick 
from the Jet Propulsion Laboratory for his support 
within the NASA SIR-B Science Investigation Team 
in providing all the input SIR-B images and 
ephemeris data. They also wish to thank at the 
Canada Centre for Remote Sensing Dr. K. Raney, R. 
Boudreau, J. Laroche, and E. Kwong for their 
professional assistance to some areas of this 
project. 
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