Mir 37 1B (37mm f2.8)
In preliminary testing I found the Mir 1B to be sharp, especially from f4, with low distortion and excellent color rendition. Shadow detail is excellent. The lens is prone to flare so use a lens hood at all times. Chromatic aberration is minimal. Focusing is smooth and precise. The aperture is almost circular and stepless, which is nice for shooting video.