Mirror Drive Lever
The MZ-S was Pentax's most advanced 35mm film camera. It features a unique control scheme that combines the simplicity of traditional rotary dials with the flexibility of modern command dials. The interface is highly customizable through Pentax user functions and can be tailored to fit the shooting preferences of almost any photographer.
The MZ-S has top-of-the-line specifications including a top shutter speed of 1/6000s, a flash sync speed of 1/180s, 6 selectable AF points, P-TTL flash metering, mirror lock-up, exposure bracketing, and matrix metering. All of this comes in a sturdy, compact package much smaller and lighter than other pro-level SLR's of the time.
Unfortunately, the MZ-S contains some internal components that are prone to failure.
- Mirror Motor Gear: The motor that drives the reflex mirror has a small plastic pinion gear press fit onto the shaft. Over time the plastic gear will crack and lose engagement with the shaft. When this happens, the camera is no longer able to drive the mirror position or charge the shutter. Pressing the shutter button results in a low whine as the motor spins but nothing else. Eventually, Pentax began building some cameras with brass pinion gears but it's hard to tell which cameras received the upgrade without disassembly. Specs for the replacement gear can be found on the parts page.
- Mirror Drive Lever: The lever located on the side of the mirror box that directly drives the mirror is also plastic. If this breaks, the mirror will be stuck in the up position but the shutter will still fire.