So, i recently got a 50-140 but i haven’t manage to get a sharp image out of it when it’s wide open. At first it seems to be failing my stability or the shutter speed, but even at higher shutter speeds i don’t get a neat image. as i stop aperture down it gets better, and it’s legendary sharpness is visible from f4 and forward, but everyone says the lens is supposed to be sharp from f2.8