KMZ Jupiter-21M 200mm f/4

Nine hundred and eighty grams. That is roughly what the Jupiter-21M weighs with its caps on, spread over 165 mm of metal tube, and it is heavier than plenty of the M42 bodies it gets screwed onto. Fit one to a Zenit and the lens, not the camera, becomes the thing your left hand is really holding. M42 has no shortage of lighter 200mm options. What this one offers in return for the bulk is a Soviet long tele that lets you focus and compose with the aperture wide open.

That last part is what the M added. M.D. Maltsev drew up the original Jupiter-21 in 1957, and it came out as an M39 preset lens: one ring sets the taking aperture, a second ring closes the blades down to it, and you turn that second ring by feel just before you fire. Between 1969 and 1973 KMZ reworked the design into the 21M and gave it a pin-actuated automatic diaphragm with an auto/manual switch. On a body with a stop-down pin, the viewfinder stays bright at f/4 and the lens closes itself at the moment of exposure, which also means open-aperture metering where the camera supports it. On a body without the pin, flip the switch to manual and use it as a straightforward stop-down lens. The Jupiter-21A took another route entirely, with an interchangeable A adapter in place of the fixed mount. Production of the 21M later moved from Krasnogorsk to VOMZ in Vologda, so copies from both factories are out there.

Optically it is a modest formula, four elements in three groups, with a sliding hood built into the barrel. Expect what a long lens of this type and age usually gives: a rendering that tends to tighten up once you close down a stop or two, and possibly some colour fringing on bright edges against dark backgrounds. Out-of-focus backgrounds at 200mm melt away without much fuss. Pull that hood forward whenever the sun is anywhere near the front of the lens. The coatings date from the same decades as the rest of it, and flare will lift the shadows before you notice it in the finder.

It focuses down to 1.8 m. At 200mm that works out to a tight face portrait, with a face roughly filling a vertical frame, and no extension tube involved. Candid portraits from across a room are the obvious use. Distant landscapes, where compression stacks ridgelines on top of one another, suit it too, as do events and sport shot from the stands.

The weight is the real cost. There is no stabilisation, and the old rule of one over the focal length puts safe handheld speeds at around 1/250 or faster, which fine-grain film in mixed light will not always give you. After an afternoon with this hanging off a strap, a monopod starts to look like a sensible purchase rather than an accessory. A tripod makes it a different lens.

For black and white at long range, the 58mm thread takes an orange or red filter to cut through haze. Enter that filter's factor in Zone Light Meter and the app folds it into the reading, so the distant hills land on a negative with real density instead of a thin, flat one.