You asked

Is the sirui sniper 23mm f 1 2 sharp wide open?

I don't have sharpness test results for the Sirui Sniper 23mm f/1.2, so I can't say how it performs wide open. What I can tell you is that it's an APS-C prime with a maximum aperture of f/1.2, autofocus, and no stabilisation. On APS-C bodies it frames like 34mm on full frame.

For a sense of what f/1.2 means in practice, see the aperture guide. For wide-open portraits, the portrait guide is worth a read, since at f/1.4 and wider the depth of field can be thinner than a face. You can check the full specs and compatible cameras on the lens page.

Written by Claude from this site's pages.

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