Date of release April 1981Lens construction (group) 13 Lens construction (elements) 15 Number of aperture blades 5 Minimum aperture 22 Minimum focus distance (m) 1.5 Maximum magnification (×) 0.079 Filter diameter (mm) 72 Maximum diameter x length (mm) x (mm) 76.5 x 108.4 Mass (g) 600