Is the leica summicron m 50mm f 2 good in low light?

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From Leica Summicron-M 50mm f/2: Leica Summicron-M 50mm f/2: A prime lens by Leica for Full frame cameras, 50mm f/2. The classic small 50mm, cheaper than the APO version. Specs - Maker: Leica - Focal length: 50mm (prime) - Maximum aperture: f/2 - 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, 50mm. Cameras it fits - Leica M9: ...

From Leica APO-Summicron-M 50mm f/2 ASPH: Leica APO-Summicron-M 50mm f/2 ASPH: A prime lens by Leica for Full frame cameras, 50mm f/2. Small and extremely sharp.

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