You asked
Is the sony fe 50mm f 1 4 gm good on aps c?
Yes, it works well on APS-C. It's a full-frame lens, so on a Sony APS-C body it frames like a 75mm lens, which is a classic portrait length. The f/1.4 aperture gives about the depth of field of f/2.1 there, so you still get a soft background with your subject sharp.
It fits every Sony APS-C body in the catalogue, including the Sony a6400 and the Sony a6700. Keep in mind that the lens is large and costly for an APS-C setup. If you want a smaller, cheaper option for people, look at a 35mm-equivalent prime, as explained on the portraits page. For a first fast prime, the lenses page has more on the choices.
Written by Claude from this site's pages.