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ASAHI Super-Takumar 50mm 1:1.4
(8 lenses / 6 groups; original optical formula without radioactive glass)
(7 lenses / 6 groups; new optical formula with radioactive thorium lens)
ASAHI Super-Multi-Coated Takumar 50mm 1:1.4
(7 lenses / 6 groups)
ASAHI SMC Takumar 50mm 1:1.4
(7 lenses / 6 groups; new optical formula without thorium glass)
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