1. A technique for adjusting a stereomicroscope for inspection of three-dimensional objects comprising the steps of: a. placing a random dot stereogram within the field of view of a stereomicroscope having a pair of optical viewing paths; the random dot stereogram being of such size that it encompasses approximately the same field of view as the zone of the object to be inspected at the desired magnification for inspection, and having left and right images which are separated by a vertical distance approximately equal to the height of the zone to be inspected on the object; the left and right images having a predetermined pattern printed thereon; b. focussing the stereomicroscope on the random dot stereogram; c. adjusting the interocular distance of the paths to match the horizontal distance between the eyes of the inspector using the stereomicroscope; d. optically filtering each of the paths with means so that the left image of the random dot stereogram appears in one path and the right image appears in the other path; e. detecting the pattern in depth on the random dot stereogram; f. removing the filtering means from the paths; and g. placing the object to be inspected within the field of view of the stereomicroscope.