Flash Synchronisation; Normal Synchronisation; Second Curtain Synchronisation (Rear Mode); Slow Synchronisation (Slow) - Metz MECABLITZ 58 AF-1 digital Mode D'emploi

18. Flash synchronisation

18.1 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.

18.2 Second curtain synchronisation (rear mode)

Some cameras offer the option of second-curtain synchronisation (rear 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.
On some cameras the rear function is not possible in certain operating modes
(e.g., certain vari- or subject programs, or with red eye reduction). In that case,
the rear mode cannot be selected, or the rear function is automatically cancelled
or ignored. For more information, refer to the camera's operating instructions.
For Group A, C, D and E cameras, it must be set on the camera (see the
camera's operating instructions). Use a tripod when shooting with slow
shutter speeds to avoid blurred images.

18.3 Slow synchronisation (SLOW)

A slow exposure (SLOW) gives added prominence to the image background at
lower ambient light levels. This is achieved by adjusting the shutter speed to the
ambient light. Accordingly, shutter speeds that are slower than the flash sync
110
speed (e.g., shutter speeds up to 30 sec.) are automatically adjusted by the
camera. Slow synchronisation is activated automatically on some camera
models in connection with certain camera programs (e.g., a night shot pro-
gram, etc.), or it can be set on the camera (see the camera's operating instruc-
tions). No settings are necessary on the flash unit, nor is there any display for
this mode.
Slow synchronisation (SLOW) is set on the camera (see the camera's ope-
rating instructions). Use a tripod when shooting with slow shutter speeds
to avoid blurred images.

18.4 Automatic FP high-speed synchronisation

Various Group E cameras (D2Hs and D200, for example) support automatic FP
high-speed synchronisation (see the camera's operating instructions). This flash
mode makes it possible to use a flash unit even with shutter speeds that are
faster than the flash sync speed. Interesting results may be achieved in this mode
when, for example, a wide open aperture (e.g., f/2.0) is used to limit the depth
of field in portrait shots taken in very bright ambient light. The flash unit sup-
ports high-speed synchronisation in i-TTL, i-TTL-BL and M flash modes.
For physical reasons, however, FP high-speed synchronisation significantly redu-
ces the guide number and the maximum flash range. Be sure to note, therefore,
the flash range on the LC display of the flash unit. FP high-speed synchronisa-
tion is activated automatically if a shutter speed faster than the flash sync speed
is set on the camera, whether manually or automatically by the exposure pro-
gram.
Note that in the case of FP high-speed synchronisation the guide number
of the flash unit also depends on the shutter speed. The faster the shutter
speed, the lower the guide number.
Automatic FP high-speed synchronisation is set on the camera (see the camera's
operating instructions). „FP" will then also appear on the flash unit's display
panel, for example.