Nikon SB-50DX Speedlight compact flash. Works with 35mm and digital Nikon cameras. Covers 14mm and longer lenses. Non-rotting front element. Seikonic L-608 flash meter with zoom and digital display.
Measures flash and ambient light.
See Sigma cameras for full report. Test target was a chart I made several years ago for testing my own lenses. Chart includes large and small letters, numbers, lines, and dots, in center and corners, as well as several newspaper cutouts. Chart also includes several different color fabrics for testing color and contrast. Test slides were examined on a light box with a high quality 8X loupe to check overall sharpness and color.