User manual
Table Of Contents
6.
Built-in
Flash
Synchronize,.
The Flash
Synchronizer
concealed
within
the
body
of
theCanon
Camera
Model
IV
and
IV-F
are
so
assembled
as
to
synchronize
precisely
with
not
only
flash
bulbs
of
focal
plane
type,
but
also
of
all
peak
types
(made
nat
for
focal-
plane
shutter
but
primarily
for
between-the-Iens
shutter).
Speedlight
unit
can
equally
be
used
provided
the
unit
has
a
device
with
which
discharge
timing
can
be
delayed
between
the
range
of
15
and
100
milliseconds*.
The
synchronizer
consists
of
two
electrical
circuits:
one
is
the
High
Shutter
Speed
Circuit
using
shutter
speeds
from
1/25
to
1/1000
sec.
for
focal
plane
bulbs
such
as
GE
No.6,
31
;
Sylvania
FP-26,
2A,
etc.;
and
the
other
is
the
Slow
Shutter
Speed
Circuit
using
I/S
sec.
(or
slower)
for
various
peak
type
bulbs
such
as
GE
No.5,
11
22,
SM;
Sylvania
No.
0,
2,
25,
40,
SF,
etc.
Open
par;e
52
{or s'
chematic
diagram
of
the
Built·in
Flash
Synchronizer.
High
Shutter
Speed
Synchronization
When
the
shutter
releae
button
is
pressed
the
closure
of
contact
C
and
the
movement
of
the
first
curtain
* 1 millisecond= 1 /1
000
second
39