Xenar 24cm f/4.5 (HK 7)

Schneider’s contribution to the HK 7’s lens set, and the reason Hasselblad Historical’s account names three German makers rather than one: Zeiss, Schneider and Hugo Meyer all supplied glass to a camera assembled in Göteborg.

Ross Aktiebolag of Göteborg was the company Victor Hasselblad ran through the war, building aerial cameras for the Swedish air force, and it is where the firm that later made the 1600F learned its trade. Ross built the bodies and, unusually, the shutters; it made no glass at all. The lenses came from Germany — Zeiss, Schneider and Hugo Meyer — and Hasselblad Historical notes that no documentation has been found describing how they were imported into a neutral country that badly needed optics and rather more badly needed to be left alone.

The Xenar is Schneider’s Tessar — four elements in three groups, the same arrangement Zeiss patented and everyone else built once the patent lapsed. At 24cm on the HK 7’s 7×9cm frame it is a moderate telephoto, one of the longer focal lengths a crew could fit when altitude demanded it. Nothing Ross fitted was anti-reflection coated; coating reached Swedish military optics after the war, and these lenses date from before it.

One habit of the Ross shop matters to anyone who finds one of these lenses loose. The mounts were hand-tuned to fit a particular camera, and the protective barrel was then engraved with that camera’s serial number. A lens from one body will not necessarily seat correctly on another of the same model, which is why these are worth far more still attached to the camera they were fitted to than separated from it.

Hasselblad Historical’s account of the Ross cameras is the only substantial source on them, and its author marks several specifications as information requested — an open call to readers for detail he does not have. Maximum aperture, weight, element count and production quantities for this lens are among the figures that no published source gives, so what is recorded here is deliberately short.