Canon MACRO RING LITE MR-14EX II Mode D'emploi page 25

Modeling FlashN
When the camera's depth-of-field preview button is pressed, the flash
fires continuously for 1 sec. This feature is called "modeling flash." This
is effective for checking shadow effects on the subject and the lighting
balance. Modeling flash can be fired during wireless multiple flash
shooting (p.44) as well.
To avoid degrading and damaging the flash unit due to overheating, do
not fire the modeling flash more than 20 times continuously. After firing it
20 times continuously, allow a rest time for at least 10 min.
If the modeling flash is fired more than 20 times continuously, the safety
function may activate and restrict flash firing. If this happens, allow a rest
time for at least 10 min.
During Live View shooting, firing modeling flash (by operating the camera)
is not possible.
Modeling flash (by operating the camera) is disabled when using the flash
unit with EOS M2, EOS M, EOS Elan II/Elan II E/50/50E, EOS REBEL K2/
3000V, EOS REBEL XS N/REBEL G II/3000N/66, EOS REBEL 2000/300,
EOS REBEL G/500N, EOS IX, or EOS IX Lite/IX 7. Set C.Fn-02 to 1 or 2
(p.61), and fire modeling flash using the test flash button.
Modeling flash can be fired using the test flash button (C.Fn-02/p.61).
Color Temperature Information Transmission
This function optimizes the white balance during flash shooting by
transmitting the color temperature information to the EOS DIGITAL
camera when the flash fires. When you set the camera's white balance
to <A> or <Q>, the function is enabled automatically.
See the specifications in your camera's instruction manual to find out if
it is compatible with this function.
Using E-TTL II and E-TTL Autoflash by Shooting Mode
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