What are the alternatives to the voigtl nder super wide heliar 15mm f 4 5 aspherical iii?

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From Voigtländer Super Wide-Heliar 15mm f/4.5 Aspherical III: Voigtländer Super Wide-Heliar 15mm f/4.5 Aspherical III: A prime lens by Voigtländer for Full frame cameras, 15mm f/4.5. Specs - Maker: Voigtländer - Focal length: 15mm (prime) - Maximum aperture: f/4.5 - Made for: Full frame sensors - Mounts: Sony E, Leica M, Nikon Z - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Sony E, Leica M, Nikon Z): as marked, 15mm. - On APS-C (Sony E, Nikon Z): ...

From Voigtländer Ultra Wide-Heliar 12mm f/5.6 Aspherical III: Voigtländer Ultra Wide-Heliar 12mm f/5.6 Aspherical III: A prime lens by Voigtländer for Full frame cameras, 12mm f/5.6. Discontinued, but common used.

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