Shooting with the new Sigma 45mm F2.8 for L-mount, I realised the same thing I did when I first shot anamorphic at F5.6. Beautiful rendering matters, not just wide open, but at slower apertures. This doesn't get enough attention! Sometimes I want to see that background, and not have it completely creamed out, but neither do I want to give up the '3D' look or beautiful out of focus rendering and fall-off. What is the best rendering lens at F4? I doubt you'll find answer on Goo