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a measuring preflash is fired right before the instant of exposure to establish
the reflecting characteristics of the subject. As a result of the weighted multi-
zone reading taken by the camera’s sensor a partial light output level is
transmitted and set on the flash unit. The subject is then exposed by the sub-
sequent main flash at the selected partial light output level. The measuring
preflash does not contribute to the exposure of the subject.
To enable activation of the E-TTL flash mode on the flash unit, a com-
plete data exchange must have taken place between the flash unit
and the camera. For this purpose, the camera’s shutter release must
be held lightly depressed for a few seconds after the flash unit and
camera have been switched on.
Most digital cameras support the E-TTL flash mode only in the full auto
mode (or AUTO), program “P”, “Av”, “Tv” and the programmed ima-
ge control modes. Other flash modes such as normal TTL or manual M
or MLo are not possible in these camera modes. The manual M or MLo
flash mode is supported by the digital cameras only in the camera’s
manual mode “M”. Please also refer to the camera’s operating
instructions.
For system-inherent reasons no reflector attachments (such as diffusers,
bouncers, colour filters, a.s.o.) can be used when the flash unit is in E-TTL
mode with digital cameras, as this will result in faulty exposures!
Setting procedure for the E-TTL mode
With some cameras the E-TTL mode is automatically activated on the
flash unit when the green full auto mode or a programmed image
control mode is selected.
• Turn on the flash unit by its main switch.
• Continue depressing the “Mode” key until “E-TTL” flashes on the LC dis-
play.
• The setting becomes immediately effective. The LC display returns to its
normal state after approx. 5 sec.
Pronounced differences in contrast such as a dark subject in snow make it
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necessary to correct the exposure setting (see 4.2).
4.1.2 Automatic TTL / E-TTL fill-in flash in daylight (Fig. 5 and 6)
Most camera models automatically activate the fill-in flash mode (see the
camera’s operating instructions) when in Green Full Auto Mode, program „P“
or Programmed Image Control Mode in daylight (see the camera’s operating
instructions).
Fill-in flash overcomes troublesome dense shadows and produces a more
balanced exposure between subject and background with contre-jour shots.
The camera’s computer-controlled metering system sets the most suitable
combination of shutter speed, working aperture and flash output. For this
purpose, the flash unit is operated in the TTL or E-TTL flash mode.
Ensure that the contre-jour light source does not shine directly into the
lens as this will mislead the camera’s TTL metering system!
In this instance there is no setting or display on the flash unit for TTL fill-in flash.
4.2 Manual TTL / E-TTL flash exposure correction
The TTL auto flash mode of most cameras is matched to a 25% degree of
light reflection by the subject (average amount of light reflected by subjects
shot with flash). Consequently, a dark background that absorbs a great deal
of light, or a bright background that reflects a great deal of light, can result
in under or over exposure, respectively.
To offset this effect a correction value can be set on some cameras to manual-
ly match the TTL or E-TTL flash exposure with the photographic situation. The
extent of correction depends on the contrast prevailing between subject and
background!
A dark subject in front of a bright background: Positive correction value.
Light subject in front of a dark background: Negative correction value.
Correction value settings can change the maximum flash range indicated on
the LC display and match it to the given correction value (depends upon the
camera model)!
Exposure correction by changing the lens diaphragm is not possible because the
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