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How sharp is the ttartisan m 100mm f 2 8 bubble bokeh?

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From TTArtisan M 100mm f/2.8 Bubble Bokeh: TTArtisan M 100mm f/2.8 Bubble Bokeh: A prime lens by TTArtisan for Full frame cameras, 100mm f/2.8. Designed for soap-bubble bokeh highlights. Specs - Maker: TTArtisan - Focal length: 100mm (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, 100mm. Cameras it fits - Leica M9: 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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