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Tokina SZX 400mm f/8 Reflex MF Lens for Canon EF SZXMF400-C B&H
SZX 500mm f/8 Reflex for Canon EF Mount – Tokina Lens USA
A bit of history about Canon and catadioptric (mirror) lenses
Canon: new L-series zoom and two telephotos for the masses by Jose Antunes - ProVideo Coalition