[i]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 [i]a moderate wide angle lens with slightly above average performance This is a tamron adaptall prime lens.
[i]this is an absolutely superb optical design which features a three element focus group incorporating one low dispersion (ld) element, plus a five [i]this was one of tamron's best selling lenses throughout the early to mid 1980s for good reason it successfully combined a moderate price with ab This is a tamron adaptall zoom lens.
This is a tamron prime lens. Overall somewhat above average performance within its class, plus several notab Reviews of lenses by sigma, tamron, tokina, zeiss, zenitar, and others designed for pentax cameras Comprehensive pentax lens database with specifications and user opinions.
This is a tamron zoom lens.