by ʇolɐǝz ǝɥʇ qoq

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I was just reading the manual that came with my new flash and stumbled over this warning:

14.3 Flash capacitor forming
The flash capacitor built into the flash unit undergoes physical change if the unit is not switched on for a prolonged period. For this reason it is necessary to switch the unit on for approximately 10 minutes at least once every three months.

Is this seriously a problem? How long does a flash have to sit idle before it has issues?

What kind of issues would I see? Slower recycle times? Inability to recycle? Total failure to power on?

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If you use it less then one time every three months, you should sell it. I'll give you a few bucks :) – dpollitt Jan 7 '12 at 18:56
@dpollitt Does that mean that a flash that stays in a store for more than 3 months, will be degraded when I buy it? – kazanaki Mar 31 at 8:30
up vote 22 down vote accepted

With electrolytic capacitors, disuse can cause slower discharge, and longer recycle times, which can be restored by firing and recycling the flash a few times.

If you don't use them for a long period, the non-conducting dialectric can break down to the point they will short circuit.

Periodically turning it on will charge the conductive plates and this will prevent the dialectric from breaking down.

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The renowned flash makers from Metz gave the simple advice, to switch on a rarely used flash gun st least every 6 months for "re-forming" the flash capacitor. Just switch the flash on and leave it that way for at least 10 minutes and don't fire it. If you don't need it after re-forming, than just switch it off.

I myself have never experienced any problem with flash guns and even prolonged storage. I use some of mine quite regularily, but others very rarely. But when I finally use them, they simply work. Though I try to prepare them, with that simple re-forming procedure.

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Can you cite/link a reference? Because this is the opposite of what the Strobist tells you to do. – inkista Mar 31 at 20:58

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