You asked
Is the ttartisan 500mm f 6 3 good on aps c?
Here is what the site says about that.
From TTArtisan 500mm f/6.3: TTArtisan 500mm f/6.3: A prime lens by TTArtisan for Full frame cameras, 500mm f/6.3. Specs - Maker: TTArtisan - Focal length: 500mm (prime) - Maximum aperture: f/6.3 - Made for: Full frame sensors - Mounts: Sony E, Fujifilm X, Nikon Z, Canon RF, L-Mount, Canon EF, Nikon F - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Sony E, Nikon Z, Canon RF, L-Mount, Canon EF, ...
From Focal length converter: Aperture and depth of field: The f-number sets exposure, and that doesn't change with sensor size: f/2.8 gives the same brightness on a phone as on medium format. Depth of field does change. At the same framing, multiply the f-number by the crop factor to get the full-frame aperture with the same depth of field: f/1.8 on APS-C gives about the background blur of f/2.7 on full frame, and f/1.8 on Micro Four Thirds about ...
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