Specifications

SHUTTER BUTTON LOCK
The shutter button lock lever is for your convenience while
you are making a particularly long exposure using the B
shutter speed setting. After depressing the shutter button,
turn the lock lever (which is on the collar at the base of the
shutter button) so that the letter "L" is visible. When the
exposure time is up, move the lock lever back to its original
position. This automatically releases the shutter button. In
addition to making "Time" exposure, the lock lever is also
used to turn off the meter circuit and simultaneously
prevent accidental release of the shutter.
MANUAL SHUTTER OPERATION
The two silver oxide batteries in your MX are used only for powering the
exposure meter; the shutter mechanism is a totally manual operation.
Therefore, your camera can still be operated even if the batteries have worn
out. If the batteries have worn out and the exposure meter is no longer
functioning, you must determine the correct combination of shutter speed and
aperture size yourself, from your own experience. Also, packed in with most
types of 35mm film is a data sheet with suggestions for determining the
correct exposure in a variety of situations.
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