Minolta MD VFC Rokkor 24mm f/2.8

The plane of focus on this lens is flat only while the VFC ring sits on its center diamond. Move the ring left of the diamond and the sharp zone curves into a bowl, its corners pulling in nearer the camera than the point you focused on. To the right, the bowl inverts into a dome. Rokkor Files gives the numbers: with the lens focused at 70 cm and the ring on the right-hand red mark, the field reaches out to 4 meters at the corners, so a close subject in the middle and the background at the edges both render sharp, even at full aperture. You can watch the curve change in the finder as you turn.

Minolta's own 1980s lens catalogue claims the idea outright: no other company, it says, made a variable field curvature lens. The MC VFC Rokkor came first, in April 1975. This MD VFC Rokkor followed in September 1977 and stops down to f/22, where the MC version stopped at f/16; a plain MD VFC arrived in January 1982. The company's lens data lists all three at 60,000 yen. Rokkor Files ranks it with the 35mm Shift CA and the 85mm Varisoft as Minolta's "Big 3" of special lenses.

Under the ring sits the regular 24mm f/2.8 formula: nine elements in seven groups, with floating elements. At the median setting, the catalogue says, it is corrected to render a flat subject sharp. Testing the 1982 plain MD version, which uses the same 9-element design, minolta.su found no chromatic aberration even wide open and called the geometry ideal. By its reckoning the lens is ready for landscapes from f/5.6 and for close-up work from f/2.8.

Minolta aimed the ring at rounded or recessed subjects, and its catalogue says the payoff comes mostly at close range and wide apertures. Think of the surface of a ball, or a group seated around a table, shot close and wide open where depth of field cannot stretch from the nearest face to the farthest. Far subjects are another matter. At f/16 on a distant view, depth of field already covers most of what the ring could do, so a landscape shooter pays extra for a control that rarely leaves the diamond. Forget to send it back there, and the next flat wall you shoot wide open comes back with soft corners.

Rokkor Files and minolta.su land in the same place on value. The first calls it a very expensive lens whose higher cost is hard to justify unless you need the VFC feature or collect lenses. The second sends anyone who does not need the ring to the standard MD 24mm f/2.8, which it calls cheaper, lighter and optically better. Neither review makes this point, but if you want the same nine-element floating glass without the ring, the closer match is the MD W.Rokkor 24mm f/2.8. Nor is the VFC premium new: Rokkor Files recorded an MD Rokkor-X copy selling for US$622 on eBay in May 2003.

The 55mm thread does not rotate, and for daily shooting that matters more than any collector premium. A polarizer or a grad stays where you set it while you focus. For an ND or a polarizer, enter the filter factor in Zone Light Meter and the handheld reading already carries the loss, since the camera body, not the lens, times the exposure.