Zeiss Milvus 85mm f/1.4 – test results
Resolution
Corner definition is never very far behind that of the centre of the imaging circle, even at the widest apertures, which is a sure sign of a quality lens. That the resolution readings are so high only makes this more incredible. The best resolution comes at f/4, while frame uniformity is better at f/5.6 and onwards. Even fully closed, resolution is very high.
Shading
Vignetting is dramatic when the lens is at its widest settings, with the corners very noticeably darkened by about 1.6 stops at f/1.4. Close down to f/2 and the light fall-off practically halves, to around 0.9 stops. Some shading still exists at f/2.8, but is effectively gone at f/4. For portraiture the vignetting can be used creatively, although realistically work will start at f/3.5-f/4, otherwise not enough of the face will be in focus.
Curvilinear distortion
The degree of distortion present in images from this lens isn’t worth writing about. Even technical operators will be happy, but I suspect most users will be shooting natural subjects in which distortion is rarely obvious anyway.