stereocomparator
noun
stereo·comparator
"+
: a stereoscope used in making topographic measurements by the accurate comparison of stereoscopic photographs taken with an instrument having very great distance between the objectives or used in astronomy to detect small motions and brightness changes by stereoscopic examination of two photographs of the same celestial area taken at different times
Word History
Etymology
International Scientific Vocabulary stere- + comparator; originally formed as German stereokomparator