Bronica S2 repair & common faults
Excellent coverageThe Zenza Bronica S2 is an early 1960s Japanese medium format SLR built around a focal-plane shutter and an interchangeable Filminder film back, an unusual layout for the era that borrowed its lens mount and optics from Nikon. Its reliability hinges on the mechanical film tensioning system in the back, the mirror and diaphragm linkage, and the cloth focal-plane shutter itself, all of which are original 1960s mechanisms with no electronics involved.
Horizontal cloth focal-plane shutter · Fully mechanical, no metering · Interchangeable Filminder 120 roll film back · Nikkor auto-diaphragm lens mount · Instant-return mirror
Common Bronica S2 faults
Bronica S2 shutter won't fire
Usually points to the wind and shutter-cocking mechanism being out of sync with the film back, since the S2's crank only performs whichever of winding the shutter or advancing the film is still outstanding. It can also mean the dark slide hasn't been fully withdrawn, which mechanically blocks the release. Check the dark slide is pulled right out before assuming a fault inside the body.
Bronica S2 mirror stuck down or slow to return
The S2's mirror moves forward and down rather than flipping up, on a linkage that ages and stiffens with old lubricant. A mirror that stays down, drops back slowly, or hangs partway after the exposure usually means that linkage or its return spring is losing tension. This is a common fault on cameras that have sat unused for years and is a job for the bench.
Bronica S2 diaphragm not stopping down or not reopening
The lens diaphragm should snap shut to the preselected aperture on exposure and spring straight back open. If the screen stays dark, stays dim, or the diaphragm hangs closed after firing, the automatic linkage between body and lens has stuck or lost its return action. Confirm the depth-of-field preview button isn't jammed in the pressed position before assuming a lens fault.
Bronica S2 Filminder back won't lock or film not advancing
The back is designed to refuse removal unless the dark slide is inserted, and to refuse exposure unless it's withdrawn, so a back that won't seat, lock, or a film that won't advance often traces to that interlock being out of adjustment or the gear wheels between holder and back not meshing properly. Check that the film holder is seated fully before locking the cover.
Bronica S2 film not lying flat, scratched or light leaks
The S2 relies on a tensioning system that releases pressure on the film while winding and reapplies it once in position, so scratching, uneven flatness, or fogged frames usually mean that system, or the light-trap curtain around the back, is worn or damaged. This is a back-specific fault rather than a body problem, and worth flagging with which back is affected.
Stuck on your Bronica S2?
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Try it now ›Scatto is a reference tool for people who service film cameras. It explains mechanisms and quotes service data, but it cannot see your camera at the bench, so verify anything load-bearing before you act on it.