You asked

Is the sigma 12mm f 1 4 dc contemporary sharp wide open?

I haven't got a sharpness rating for the Sigma 12mm f/1.4 DC Contemporary at f/1.4, so I won't guess. What I can tell you is that it's an APS-C prime with f/1.4 as its widest setting, about 18mm equivalent on Sony E and Fujifilm X. It has autofocus but no stabilisation.

Wide open is the hardest place for any fast lens to be sharp, so look for independent test results before you buy. If you want to understand what f/1.4 does to your pictures, the Lenses guide covers aperture and background blur. The full specs and the list of compatible bodies are on the Sigma 12mm page.

Written by Claude from this site's pages.

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