Canon FTB repair & common faults
Excellent coverageThe FTB was Canon's mid-range SLR through the early to mid 1970s, built around a fully mechanical, all-speed focal-plane shutter with a match-needle CdS meter layered on top for exposure guidance. The shutter runs without a battery at all; the cell only feeds the meter. Most faults trace back to the age of that meter circuit or to lubricants inside the shutter and mirror box stiffening after fifty-odd years.
Match-needle CdS TTL metering, centre-weighted · Mechanical cloth focal-plane shutter, all speeds work without a battery · Meter powered by a 1.35V mercury cell, long since discontinued · FD mount, FL lenses usable stopped down
Common Canon FTB faults
Canon FTB meter needle won't move
A needle that sits still, pinned at one end, or drifts regardless of light usually means the meter circuit isn't getting clean power, not that the CdS cell has failed outright. Worth trying a fresh cell first and checking it's seated correctly. Beyond that it's a continuity or corrosion issue in the battery chamber or switch, common on a camera this age and generally straightforward to trace.
Canon FTB meter reading wrong exposure
CdS cells drift with age and heat cycling, so a meter that's consistently a stop or more out, rather than dead, points to a tired sensor or a mismatch from the wrong replacement cell voltage. It won't correct itself, but it's a calibration and component issue rather than anything structural, so the shutter and body underneath are usually sound.
Canon FTB shutter sounds slow or dragging
A shutter that sounds noticeably lazy on the slower speeds, or gives visibly overexposed frames at 1/30 and below, is almost always old lubricant thickening in the escapement rather than a broken part. It tends to worsen gradually, and the faster speeds often still sound fine even once the slow end has started dragging.
Canon FTB uneven exposure across the frame
A frame that's dark or light in a band, usually worse at higher speeds, means the two shutter curtains have drifted out of matched timing as they cross the frame. It's a mechanical wear issue in the shutter, not a light leak, and it tends to be consistent rather than random once it starts, which is a useful way to tell the two apart.
Canon FTB mirror stuck up or slow to return
A viewfinder that stays black after firing, or a mirror that returns slowly instead of snapping back, points to old damper foam or lubricant in the mirror box rather than the shutter itself. It's a common age-related fault on cameras that have sat unused for long stretches and doesn't usually indicate anything more serious.
Canon FTB light leaks on film
Fogging or streaking near the edges of frames, especially in bright conditions, is almost always perished foam seals around the film door rather than anything wrong with the shutter. It affects every roll shot until addressed, and it's one of the more common faults on any camera of this age. Worth checking the door seals for crumbling foam before assuming anything more serious.
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