The Enneads

This image shows a complex geometric test pattern used for photographic digitization quality control. The pattern is contained within a large rectangular border. In the center is a circle composed of multiple fine concentric rings. A thin vertical and horizontal crosshair intersects at the exact center and extends to the frame edges. Four diagonal lines radiate from this center point toward each corner of the rectangular frame. On the left and right sides, pointing inward toward the center, are large triangular shapes filled with fine horizontal hatching. Similar segments of concentric curves or nested squares with parallel hatching are located in each of the four corners and at the top and bottom center of the frame. Positioned below the central circular motif is a horizontal ruler scale. This scale is marked with vertical lines and numbered from 0 to 10.