Zeiss biogon t 21mm f 2 8 zm vs voigtl nder color skopar vintage line 21mm f 3 5 aspherical?

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From Voigtländer Color-Skopar Vintage Line 21mm f/3.5 Aspherical: Voigtländer Color-Skopar Vintage Line 21mm f/3.5 Aspherical: A prime lens by Voigtländer for Full frame cameras, 21mm f/3.5. Specs - Maker: Voigtländer - Focal length: 21mm (prime) - Maximum aperture: f/3.5 - Made for: Full frame sensors - Mounts: Leica M - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Leica M): as marked, 21mm. Cameras it fits - Leica M9: Full frame - Leica M9-P: Full frame - [Leica ...

From Zeiss Biogon T* 21mm f/2.8 ZM: Zeiss Biogon T* 21mm f/2.8 ZM: A prime lens by Zeiss for Full frame cameras, 21mm f/2.8. Specs - Maker: Zeiss - Focal length: 21mm (prime) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Leica M - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Leica M): as marked, 21mm. Cameras it fits - Leica M9: Full frame - Leica M9-P: Full frame - [Leica ...

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