You asked
Is the sigma 28 45mm f 1 8 dg dn art good on aps c?
On APS-C, the Sigma 28-45mm f/1.8 DG DN Art is a good fit. It frames like a 42-68mm lens on full frame, which is a useful standard-to-short-telephoto range for people, food, and everyday walking-around shots. Because f/1.8 on APS-C gives about the background blur of f/2.7 on full frame, you still get a soft background with people. It's not stabilised, so keep an eye on your shutter speed in dim light.
It works on Sony APS-C bodies such as the Sony a6400, Sony a6700, and Sony ZV-E10 II. If you want more reach for portraits, a 56mm f/1.2 to f/1.4 plays the role an 85mm does on full frame, as I explain in portraits. For the aperture maths, see the focal length converter.
Written by Claude from this site's pages.