The zeiss 50mm f15 t c sonnar zm lens is a standard focal length with special qualities which make it well suited for portraiture the c designation in the title means both compact and classic the lens design and aperture geometry reflect its predecessor from the 1930s and this new lens stays true to its heritage physically resembling the objectives of by gone days the excellent flare control inherent of the sonnar lens design is further optimized with the zeiss t anti reflection co