Model 55BB
SP Symbol500mmF/8
Tele-Macro Catadioptric
Tamron SP Adaptall-2 500mm F/8 Model 55BB Mirror Lens

Tamron SP 500mm F/8 Mirror Model 55BB: This later version SP 500mm F/8, introduced in 1983, is an optically revised version of the original model 55B lens first introduced in 1979. The major optical design change is the switch to a constant thickness meniscus main mirror in order to reduce close focusing spherical aberration. The change in the main mirror design also necessitated changes for the two smallest lenses located within the middle of the optical design. This model 55BB also discards the earlier model's detachable tripod mount and the set of four filters for B&W photography. The later model 55BB is also readily distinguished from the original model by its diamond knurled rubber focus grip and the lack of the locking screw used on the earlier model 55B's built-in rotating tripod mount ring. Thus this lens does not feature any built-in tripod mount whereas the original lens featured a detachable tripod mount.

We haven't had the opportunity to compare both optical versions since the fact that the optical design had changed slightly completely escaped our attention until now. Nevertheless this is now a high priority on our list in order to answer two questions: Which lens is sharper across the field for distant subjects? Which lens is sharper for tele-macro work? It may turn out that the earlier version is slightly superior for long distance photography while the later version likely is somewhat superior for tele-macro work. Why do we say this without having compared these two lens versions? Because at least in the early 1980s Tamron, unlike many other competitors, was NOT known for introducing revised lens designs that offered inferior overall performance. This is because Tamron was still trying to increase consumer acceptance and market share by offering improved optics.

Please see the 55B link for our review and Modern Photography's test results of the earlier version of this lens.

Lens Specifications:

Lens Model 55BB
Focal Length 500mm
Aperture Range f/8
Angle of View
Optical Construction
(Groups / Elements)
4 / 7
Min. Focus from Film Plane 66.9" (1.7m)
Macro Mag. Ratio [w/2X Converter] 1:3 [1:1.5]
Filter Size 30.5mm (rear), 82mm (front)
Diameter 3.3" (84mm)
Length at
[w/Nikon mount]
3.4" (87mm)
[3.6" (91.5mm)]
Weight 21.0 oz. (595g)
Lens Hood Screw-in type, retractable.
Accessory Accepts SP 2X tele-converter #01F. Supplied with lens hood, case.
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