<p>In the Nikon line, a Nikkor 50/2 H.C converted to AI. I formerly used it on a D200 before I gave that camera to my grandson, and now I use it on a Fuji X-T1. I use the Metabones Speed Booster which, with the usual 1.5 multiplier for an APS-C camera, gives the lens the field of view of a normal 50mm lens on full frame with the added advantage of an extra stop of light for focusing.. Why do I like the lens so much? It's hard to say - I just seem to prefer the pictures that I take with it to those taken with my other lenses. It's probably a combination of a number of lens characteristics that I find pleasing. Plus, I like manual focus, and the split image focusing with the Metabones and the f/1.4 make manual focusing extremely easy.</p>