Nikon SB-900 Overheating Warning? – Paul Grupp:
My wedding photography partner and I have two SB-900s. While I agree that the sky is NOT falling, the fact is, the situation is less than ideal. When we're shooting in bounce mode where the distances are great enough to require full-power pops, the flash does get pretty annoying, flashing a warning on the LCD, and playing that irritating 3-tone warning.
My GUESS is that the thing is not going to melt down any faster than other flashes, but let's face it — the default setting of the warning circuit combined with the other warnings does not inspire confidence in those of us who worry about such things.
For Nikon to be taken seriously in the event flash world, they're going to need to address this issue in the relatively near future.
IMHO, the SB900 is a step forward compared to any other flash on the market — except in this one area.
Paul Grupp adds that the SB900 user manual does say that the protection function can be turned off:
The SB900 ships with a VERY conservative shut-down function enabled — the default setting is "uber-protection ON."
Turn off this function, and the flash will seem less like your enemy. With the protection on, the flash is unusable in any professional event capacity.
I agree that the achilles heel of the SB900 is its approach to thermal issues and self-protection, but if you turn off the protection circuit, it at least becomes usable, if not a complete success in a fast-pop environment. (It'll still flash a warning on the LCD and play an extremely annoying three-tone warning when it thinks it's too hot).
Put me down as a huge fan of the "new Nikon's" products like the D3X, D3, D700, 12-24/2.8, 24-70. These are the hits.
The SB-900 would have been a hit, IMHO, if it wasn't for the over-conservative thermal engineering.
The newish AF-S 50/1.4 G is in the same category — would have been a hit, but for it's outrageously sluggish AF performance.
Joe Federer confirms that he turned off Thermal Shutdown on his own SB900:
First thing I did when I got mine.
Mine's never ceased to fire.
(edit: I should mention I generally fire over 1000 flashes per reception – around 200-300 an hour).
Joe also gives the following tip:
You can turn off the beep, too, [...]