Is the sony e 11mm f 1 8 sharp wide open?

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From Sony E 11mm f/1.8: Sony E 11mm f/1.8: A prime lens by Sony for APS-C cameras, 11mm f/1.8. Specs - Maker: Sony - Focal length: 11mm (prime) - Maximum aperture: f/1.8 - Made for: APS-C sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On APS-C (Sony E): like 16mm on full frame; f/1.8 gives about the depth of field of f/2.7 there. - On the larger-sensor bodies of Sony E: ...

From Lenses: Aperture: The f-number says how wide the lens opens. Smaller numbers let in more light: f/1.8 lets in about ten times as much light as f/5.6, more than three stops. A wide aperture means faster shutter speeds in dim light and more background blur. Zooms with a constant aperture, like a 24-70mm f/2.8, keep the same exposure throughout the zoom range; cheaper zooms get darker as you zoom in.

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