AUTOMATIC REGISTRATION ELECTRONIC STEREOSCOPE (ARES) 
ARES is the first instrument in a proposed photogrammetrie system and 
one which, by virtue of its involvement in all zero-, first-, and second- 
order transformations, is an ideal vehicle for the description of automatic 
registration in general. 
ARES is, as the name implies, primarily a stereoscope. It differs from 
prior stereoscopes in that the following operations are performed automati 
cally by electronic means: 
(1) Y parallax is reduced essentially to zero at all points in the 
image area. 
(2) X parallax is reduced at all points to values compatible with com 
fortable ocular convergence. 
(3) The tonal range of the observed image and the sine wave response 
characteristic of the imaging system are both subject to automatic adjust 
ment to improve the appearance and interpretability of the stereo model as 
seen by the operator. 
Before proceeding with the description of the electronic and automation 
features of ARES, a brief description of the mechanical and optical arrange 
ment will be given. Figure 2 is a photograph of ARES and shows the major 
structural elements. The operator observes the stereo model in the binocular 
viewer which contains separate cathode ray tubes for the right and left eyes. 
Below the table are the cathode ray tubes and lenses of the flying spot 
scanners, and immediately above the table top are the two light-collection 
systems. The transport system carrying the stereograms slides in the gap 
between the light-collection systems and the table top.