d. SLOW SPEED EXPOSURE TIMING
Slow speed exposure timing can be determined by adjusting the exposure timing for 1/15 sec (6.7 ms),
and the exposure timing for the rest (1/8-1 sec) may be determined automatically by dint of the slow
speed cam (F01). Better stability of the exposure timing can be expected if the timing for 1/15 sec is
adjusted so as to be very slightly prolonged, viz., 7-8 ms.
First, see to it that the contact between the slow speed lever (F07) and the slow speed lever actuator stud
(E45) of the coupler gear (E18) is made closer to the entrance of the opening of the governor assembly
(0G00). In other words, adjust and set the shutter exposure timing to be a little faster than 1/15 sec and
then attempt to arrive at the correct exposure timing gradually by means of repeated measuring, and you
will find this method easier for making necessary adjustment. The procedures are detailed below in the
order o
f work:
(Diagram 19
)
(1) Slightly ease the adjust plate screw (F18) (left-handed screw) and the screw (5), and rotate the top
adjust plate (F05) counter-clockwise until it reaches the lip of the screw (5).
(2) Slightly fasten the adjust plate screw (F18) to such an extent as to make (F05) rotate chafing against
the bottom adjust plate (F04) when the screw (5) is turned.
(3) Turn the screw (5) clockwise slightly to give a push to
(F05).
(4) Measure exposure timing.
(5) Repeat the procedure of 3 and 4.
(6) When the timing reaches the allowable tolerance of 7-8 ms, tightly screw in (F18).
(7) Make final measurement.
(8) Seal tightly the screw (5) with red lacquer.
Diagram 19
e. TIME
EXPOSURE
(Diagram 20)
When the shutter is released with the shutter speed dial set at "T," the 1st curtain completes its
travel, but projected part of the slow speed actuator lever (F06) hooks with the time stopper
(F03), thereby preventing the 2nd curtain from starting its travel.
When the shutter speed dial is turned to "B" or 1 1000, (F06) moves to the left by dint of the slow speed
cam (F01), separating from the stopper (F03), causing the 2nd curtain to start its travel, thereby making
time exposure complete.
During the time pace of 1.15 1 sec, (F06) actuates to the extreme right, when the speed dial is set at 1
sec. At this instant, the projected part of (F06) must actuate without contacting (F03). Bearing in mind
what has been described above, it is essential to adjust (F03) by easing the screw (3).
230-2
-18
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Summary of Contents for PENTAX S3
Page 1: ...PRODUCT NO 230 2 ASAHI PENTAX S3 SERVICE MANUAL 230 2 1...
Page 37: ...EXPLODED ILLUSTRATIONS Fig 1 230 2 37...
Page 38: ...Fig 2 230 2 38...
Page 39: ...Fig 3 230 2 39...
Page 40: ...Fig 4 230 2 40...
Page 41: ...Fig 5 230 2 41...
Page 42: ...Fig 6 230 2 42...