In article <322B913E.1AEC@humboldt1.com>, ljclark@humboldt1.com says...
>What is the relationship between the old Cosina and the...
>
> Vivitar 100-500 f5.6-8 (Series 1)
> SamYang 100-500 f5.6-7.1
> Cambron 100-500 f5.6-7.1
> Kalimar 100-500 f5.6-7.1
None.
Hope This Helps