How sharp is the voigtl nder heliar 40mm f 2 8 aspherical?

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From Voigtländer Heliar 40mm f/2.8 Aspherical: Voigtländer Heliar 40mm f/2.8 Aspherical: A prime lens by Voigtländer for Full frame cameras, 40mm f/2.8. Specs - Maker: Voigtländer - Focal length: 40mm (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, 40mm. Cameras it fits - Leica M9: Full frame - Leica M9-P: Full frame - [Leica ...

From Portraits: Aperture and background blur: A wide aperture (a small f-number like f/1.8) gives a shallow depth of field: sharp eyes, soft background. Blur also grows with focal length, with getting closer to your subject, and with putting more distance between the subject and the background. Moving your subject away from a wall often does more than a faster lens. At f/1.4 and wider, the depth of field can be thinner than a face. Stop ...

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