Fig. 13
From: High-resolution shape models of Phobos and Deimos from stereophotoclinometry
Results of the keypoint matching, keypoint distance, and limb/terminator methods applied to Phobos. a Histogram of the scale factor needed to match the model to the reference image based on the keypoint matching method for 222 images. Values < 1 indicate the model is larger than the images. The keypoint matching method indicates a 66-m accuracy and a + 44-m scale uncertainty for a scale factor of 0.996 (the model is slightly larger than the images). b Histogram of the median residual difference between the model and the reference image based on the keypoint distance method for 222 images. They keypoint distance method indicates a 50-m accuracy and a + 30-m scale uncertainty. c Histogram of the difference between the model (rendered image) and the reference image based on the limb/terminator method for 173 images. The limb/terminator comparison indicates a 59-m accuracy and a + 17-m scale uncertainty (again the model is larger than the images)