Mamiya APO A 300mm f/2.8 (645)

The APO A 300mm f/2.8 is the largest and fastest lens Mamiya made for the manual-focus 645, and by the company’s own account the first of its kind for medium format. Mamiya’s brochure and its Pro-era product sheet agree on the figures: 9 elements in 8 groups, a 13° angle of view (13°30’ on the sheet), f/2.8 to f/22, closest focus at 3.5 m for 0.10×, and 2,700 g in a barrel 139.5 mm across and 237 mm long. Filters are 43.5 mm drop-ins in a drawer behind the front group, and the lens shipped with a set of six (clear, UV, skylight, two colour-conversion filters and a gelatin holder), which is what Japanese Wikipedia’s ‘フィルター6種付属’ refers to. The barrel carries a rotating tripod collar with strap lugs, a preset-focus locking ring for jumping between two set distances, and a black built-in hood. The brochure prints a cross-section, MTF curves at f/2.8 and f/5.6, a distortion curve and an illuminance curve, all linked above.

There is one version. The 645 Pro instruction book of 1992 says the lens ‘was also designed for this camera’, and Pebble Place dates it to 1992 as well, with a US list price of $9,900 and a street price around $7,700 that October; that price rests on Pebble Place alone and the page is flagged for it. The Pro TL book of 1997 still lists it, beside the later A 500mm f/4.5 APO, and adds a practical detail: the 300 and 500 APO lenses are corrected for infrared and need no infrared index mark. Mamiya’s 2X Extender N-2 turns it into a 600mm f/5.6, which the brochure sells for sports and wildlife.

Only one review from a site this project could read covers it. Pebble Place finds it sharp at f/2.8 with a slight purplish glow on bright edges that is gone by f/4, some longitudinal colour in busy backgrounds but none in the plane of focus, and bokeh that can look ‘nervous’ behind complex scenes; the build is compared with Canon’s telephotos of the period, let down by a perishing rubber ring on the hood and a single screw holding the tripod foot. The verdict is that for manual focus it is ‘pretty darn hard to beat’, though a modern autofocus lens is the sensible choice for most people. Brian Hirschfeld reviewed it against the AF 300mm f/4.5 APO and with the 2X N converter on a Phase One IQ180, but his site now returns an error and the copy of his review at ianbfoto.com could not be fetched, so only his Flickr collection is cited. Mamiya’s own brochure quotes fashion photographer Richard Hume on ‘razor sharp, blown-out backgrounds’, which is advertising rather than a review.

Buying one means handling a 2.7 kg lens that is thirty years old. Check the hood’s rubber ring and the tripod foot screw that Pebble Place describes, that the drop-in filter drawer and the clear filter are present (the drawer sits in the light path and the lens is meant to be used with a filter in it), that the preset-focus ring locks and releases, that the collar rotates without play, and that the front element, which has no front thread for a protective filter, is unmarked. On the 645AF, AFD and DF bodies it mounts but meters only stopped down, per Wikipedia. The black Sekor C 300mm f/5.6 and ULD C 300mm f/5.6 N, at 710 g with 58 mm filters, are different lenses, as is the autofocus 300mm f/4.5 APO IF.

What remains open: a Japanese list price, the month of introduction and the discontinuation date, the blade count beyond Wikipedia’s figure of eight, whether the focusing is internal as dealers say, and a second review from a readable source.