Canon C12-8453, Service Manual

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2-12 AF-assist: (1) Method: Intermittent burst fired by built-in flash (no
patterned beam).
Fired automatically when necessary and linked to all seven focusing
points.
Effective range: Approx. 4.5 meters at center and 4 m at periphery.
Coverage: 28mm lenses.
(2) Preconditions: Fired automatically in low light (EV 4
or lower at ISO 100).
• Automatic pop-up and AF-assist light in the Full Auto, Portrait,
Closeup, and Night Scene modes.
• Disabled in Landscape and Sports modes.
• In P, Tv, Av, M, and DEP modes: Manual pop-up and firing.
* AF-assist can be enabled/disabled with C.Fn-7 (also applicable to
external Speedlites).
(3) AF-assist time, frequency, and consecutive AF assists:
20
µ
s, 28 Hz, max. 8
* AF-assist light turns off when the in-focus signal is detected.
(4) With EX/EZ/E-series Speedlites
AF-assist beam is emitted by the external Speedlite.
• SPEEDLITE 420EX: Compatible with all focusing points.
• 550EX/540EZ/ST-E2: The AF-assist patterned beam is not
compatible with top and bottom focusing points with which focus
cannot be achieved. (Compatible with the other focusing points.)
• With other EOS-dedicated Speedlites: AF-assist beam is not emitted
when an off-center focusing point has been selected. (Emitted only
when the center focusing point has been selected during automatic or
manual focusing point selection.)
3. Viewfinder
3-1 Type: Eye-level, single-lens reflex type with fixed pentaprism
and condensor lens.
3-2 Focusing screen: Fixed New Laser-matte screen with 7 focusing points.
3-3 Standard diopter: -1 dpt.
3-4 Dioptric adjustment -2.5 - +0.5 dpt.
range:
3-5 Eye relief: 19.5 mm
3-6 Viewfinder coverage: 90% vertical, 92% horizontal.
3-7 Magnification: 0.70x (with 50mm lens at infinity)
Part 1: General Information
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