Led Illumination - Canon A-1 Repair Manual

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LED illumination
Since the camera memorizes not only the exposure value
but also the light intensity of the LED display upon
pressing the AE lock button, the display may be to dim
to see eas ily when the camer a is pointed to a bright
subject after the e xposure m emory button is depressed
with the camera pointed at a dark subject.
If either shutter speed or aperture value is changed
while looking into the viewf i nder, the indication
seems to be late in responding to · change of the AT
dial . The reason is that a change of indication takes
place after 0.5 sec. This is just a matter of indica-
tion and the exposure will be correct because the
actual exposure control occures without time lag.
While metering the same subject, there is the case
that ther e will be a difference of half a step in terms
of exposure value when displayed if photographic mode
changed between shutter priority, aperture priority or
programmed AE mode . The reason is that the calculated
value is displayed for every half a step in the case
of shutter priority AE and aperture priority AE mode
while in the programmed AE mode, both shutter speed ·
and aperture value are both variable so the changeovers
do not occure at exactly the same point . (There is no
difference in the actual exposure,)
If AE photography mode is changed from one to another
while metering the same s ubject, flashing warning may
take place in the AE mode changed to.
(Example)
If an exact calculated value is 5.6 plus 1/8
though the viewfinder shows "1000 5.6" in the case
of shutter priority AE mode, display changes to
" 1000 (flashing) 5 . 6" when changed to aperture
priority AE mode. If the aperture value is set
to f/5.6 in aperture priority AE mode under the
same lighting conditions as above, the correspond-
ing shutter speed will be calculated as 1/1000
plus 1/8 and in the case aperture priority AE mode,
the display flash es i f a calculated shutter speed
is even slightly s l ower than 30 ·sec. or faster
than 1/1000 sec. For t he same reason , the display
flashes if a calculated aperture value is smaller
than the A VO of the lens used in shutter priority
AE mode . The above happens only at a point near
the limits of shutter speed (i.e. 30 sec. or
1/1000) in aperture priority AE mode and at a
calculated aperture value larger than the AVO of