Canon Speedlite 540EZ Manual page 17

V. Advanced Flash Techniques
1. Flash Exposure Compensation
The 540EZ incorporates a feature for compensating the flash exposure
independent of the camera exposure. The flash exposure can be com¬
pensated up to ±3 stops in 1/3-stop increments. By combining this capa¬
bility with the camera's exposure compensation function, you can fine
tune both the background exposure and the flash exposure to achieve a
perfect balance.
• If flash exposure compensation is set on both the camera and the 540EZ, the
540EZ's setting will override the camera setting.
• Flash exposure compensation is not possible in Full Auto mode or
Programmed Image Control (PIC) modes.
■f
Set the flash to automatic
flash control mode
(A-TTL
or
TTL).
2 Press the Select/Set button.
• The flash exposure compensa¬
tion indicator
(®)
and the
compensation value blink in the
flash unit's LCD panel.
3 While watching the flash unit's
LCD panel display, press the
plus button or minus button to
set the desired flash exposure
compensation amount.
• Each press of the plus button or
minus button (n) increases or
decreases the compensation
amount by 1/3 stop.
4
Press the Select/Set button
again so that the compensa¬
tion amount stops blinking.
• The compensation amount will
automatically stop blinking if 8
seconds elapse before the
Select/Set button is pressed.
• Even if a flash picture is taken
while the displayed compensa¬
tion amount is still blinking, the
flash exposure will be compen¬
sated according to the compen¬
sation amount.
If the subject is very small and the background is very'dark or far away, proper
flash exposure may not be achieved even if flash exposure compensation is
used. In a situation such as this, use manual flash.
Effect on exposure of each type of compensation
———.__
Effect
TTL flash exposure compensation
Changes the flash exposure of the main subject.
AE exposure compensation
Changes the exposure of the background.
Compensating the exposure by
changing the film speed setting
Changes both the flash (main subject) exposure and
the background exposure by the same amount.
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