13 Correct exposure indication
The correct exposure indication „OK"
exposed in TTL flash mode or automatic flash mode.
If no „OK" exposure indication
underexposed. You will need to repeat the shot with the next smaller f-number
(for example, f/8 instead of f/11), or the distance to the subject or reflecting sur-
face (for example with bounce flash) will have to be reduced. Note the maximum
flash range indicated on the display of the flash unit (see 14).
14 Flash range indication
The maximum flash range is indicated on the display panel of the flash unit. The
value indicated relates to subjects with a reflection factor of 25%, which applies
to most photographic situations. Strong deviations from this reflection factor, as
in the case of highly reflective or poorly reflective subjects, may affect the flash
range.
In TTL- and automatic flash mode, the subject should be in the middle third of the
indicated range. This will give the automatic exposure control sufficient scope for
compensation.
To avoid overexposure, the minimum distance from the subject should be no less
than 10% of the indicated value. An adjustment can be made to a particular
photographic situation by changing the aperture setting, for example.
In manual flash mode M, the distance that must be maintained from the subject
for correct flash exposure is indicated. An adjustment to the photographic situa-
tion at hand can be achieved by, for example, changing the aperture setting on
the lens and by selecting either full light output or „P" for a partial light output
level.
The flash range can be expressed in either meters (m) or feet (ft) according to
the chosen setting (see 7.7). There is no flash range indication in remote
mode or when the main reflector is swivelled or tilted.
96
only lights up if the shot was correctly
appears after the shot, then the shot was
Automatic adjustment of the flash range indication
The cameras transfer the flash parameters (e.g. lighting sensitivity ISO, lens focal
length, aperture and exposure correction) to the flash unit. The flash unit automa-
tically adjusts its settings accordingly. The maximum flash range is calculated
from the flash parameters and the guide number and indicated on the display.
This requires an exchange of data between camera and flash unit, effected for
example by tapping the shutter release.
15 Flash synchronisation
15.1 Normal synchronisation
In normal synchronisation the flash unit is triggered at the beginning of the shut-
ter time (first curtain synchronisation). Normal synchronisation is the standard
mode on all cameras. It is suitable for most flash shots. The camera, depending
on the mode being used, is switched to the flash sync speed. Speeds between
1/30 sec. and 1/125 sec. are customary (see the camera's operating instruc-
tions). No settings are necessary on the flash unit, nor is there any display for
this mode.
15.2 Second curtain synchronisation (2nd curtain, SLOW2)
Some cameras offer the option of second-curtain synchronisation (2nd curtain
mode), in which the flash unit is not triggered until the end of the exposure time.
This is particularly advantageous when used with slow shutter speeds (slower
than 1/30 sec.) and moving subjects that have their own source of light. With
second-curtain synchronisation, a moving light source will trail a light streak
instead of building one up ahead of itself, as it does when the flash is synchroni-
sed with the first shutter curtain. Second-curtain synchronisation thus produces a
more „natural" image of the photographic situation when there are moving light
sources. Depending on its operating mode, the camera sets shutter speeds slower
than its sync speed.
The synchronisation of the 2nd shutter curtain is set on the camera (see the
camera's operating manual)!