Nikon Autofocus Speedlight SB-24 - Manual (Page 128)

For multiple flash photography using Nikon F4 or
F-801/N8008, if the electric current in the synchro circuit
exceeds a certain level, you may not be able to take a
second shot after taking the first shot. Take care that the
combined total of the coefficients (numbers shown in
parenthesis below) for all speedlight’s used at any one
time does not exceed 20 at 20°C/68‘’F (13 at 40°C/104°F).
SB-24 (1) SB-23 (4) SB-22 (6) SB-21 (4) SB-20 (9)
SB-19 (2) SB-18 (16) SB-17 (4) SB-16 (4) SB-15 (4)
SB-14 (1) SB-12 (1)
SB-11 (1)
If you are unable to take a second shot, disconnect the
master speedlight from the camera, or turn each of the
speedlights off and on once. This resets the circuits so
you can resume shooting.
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