Canon 577 G - Manual (Page 34)

MULTIPLE FLASH
It is possible to synchronize another
Canon Speedlite, such as the 155A,
177A or 199A, with the 577G by con­
necting them together with a Y-
shaped synchro cord. Three or more
of these flashes may be fired
simultaneously by equipping those
which are not on the camera with
slave units. Y-shaped synchro cords
and slave units are optionally avail­
able on the market. The following il­
lustrations show how to make the
necessary connections.
All of the flash units, including the
577G, should be used on manual. If
the flash has an AUTO/MANU mode
switch, slide it to MANU.
The proper aperture may be found
by guide number formula (p.24)
based on an overall guide number
which can be calculated with the fol­
lowing equation:
G = \/ Gi^ -F G2^ -|- Ga^ -h ... Gn^
G = effective guide number
Gi, G
2 , G 3 ... guide number of each
Speedlite
30