Tamron 200-500mm F/6.9 Model 06A: This lens is an optical redesign of the earlier Adaptall model Z-500 and CZ-500 lens models. Its obvious, after comparing the optical designs of this lens to its predecessor, that Tamron's goal was to reduce the rather strong chromatic aberration and lateral color within the earlier optical design. Tamron's earlier Z-500 and CZ-500 models were unusual in that they were corrected for green and blue rather than red and yellow colors. This was preferable since most nature scenes predominately feature yellow and green colors, and since long distance telephoto photographs generally are affected by deep blue and UV haze. Nevertheless, the green-blue color correction in the earlier models resulted in significant amounts of red chromatic aberration and red lateral color. This significantly reduced the MTF for the earlier versions of this lens. Note that chromatic aberration and lateral color should be greatly reduced in this revised optical design, possibly making this lens an average to slightly above average optical performer within its class. Tamron's 200-500 F/6.9 model 06A lens was discontinued in 1984 with the introduction of Tamron's highly praised SP 200-500 F/5.6 model 31A lens.

Lens Specifications:

Lens Model	06A
Focal Length	200 — 500mm
Aperture Range	f/6.9 — 32, AE
Angle of View	12°~5°
Optical Construction (Groups / Elements)	8 / 14
Min. Focus from Film Plane	118" (3.0m)
Macro Mag. Ratio	—
Filter Size	82mm
Diameter	3.5" (90mm)
Length at [w/Nikon mount]	14.6" (370mm) [14.8" (274.5mm)]
Weight	97.7 oz. (2770)
Lens Hood	Built-in type, retractable.
Accessory	Accepts SP 2X tele-converter #01F. Supplied with exclusive tripod mount ring.