Originally posted by drypenn FA31, FA43, and FA77 are all developed for film, and yes, from personal experience (I have all three) they work absolutely well with digital sensors. Samsung doesn't have anything to fix in that area.
With digital full frame? I was under the impression that older lenses didn't mind throwing light onto the film at sharp angles, especially in the corners, that didn't bother film, and you had little vignetting there. With digital sensors the light has to hit the sensor at a (more or less) 90° angle... so lenses that don't do that will have bad vignetting on those sensors. If you are using those lenses on APS-C however you won't have those problems, because you are really only using the center area of those lenses. Of course it will look good, and with minimum vignetting!
The latest Samsung sensor in the NX1 isn't as sensitive to the angle at which light hits the sensor (the photodiode is closer to the "entrance"?), so there is less vignetting.