You asked

Is the ttartisan 7 5mm f 2 fisheye sharp wide open?

I don't have sharpness test results for the TTArtisan 7.5mm f/2 Fisheye, so I can't say how it performs wide open. The lens page covers what it does have: it's a manual-focus prime for APS-C, and on APS-C bodies it frames like 11mm on full frame, with f/2 giving roughly the depth of field of f/3. Its catalogue page also lists every camera it fits, including Sony E, Fujifilm X, Nikon Z, Canon RF, L-Mount and Micro Four Thirds bodies.

If you want to know what f/2 means for your shots, the aperture section of the lenses guide explains how the f-number affects light and background blur.

Written by Claude from this site's pages.

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