Flash and very cold weather

[Daianto]

A number of local acquaintances are reporting their flashes, regardless of manufacturer, are, for want of a better term, blowing up. While there could be a number of reasons for this, the one thing in common is shooting in very cold, -20C to -35C weather. In researching this I couldn't find much in the way of cold weather flash work other than the usual let your equipment slowly warm up when coming indoors.

It would seem to me that while the duration of a flash is short, the heat given off, with repeated cold weather use, may damage the flash. Would be interested in anybody's experience in this regard.

[Ellis Vener]

Back when I was assisting in the early 1980s we did a shoot in an arctic test chamber and had flash heads blow and a pack fail. My opinion is...

If the flashes are not well sealed I suspect what might be happening is moisture insde the flash is being frozen and the heat of the electricity flowing is cause the moisture to thaw and then refreeze rapidly  possibly in a place that will create a short circuit. Another possibly may have to do with electrolyte in the capacitors expanding when subjected to ultra cold temperatures for long enough and damaging the capacitor when you try to fire the flash.

[schrodingerscat]

Need to determine what is meant by 'blowing up'. And the type of flash also has a bearing.

If referring to the xenon tube, it could be thermal shock and there would be no real way to get around that, other than a temperature controlled housing. Repeated firing of the flash can also cause the tube to fail in a spectacular fashion.

if referring to the flash just failing to work, that would probably be from pushing it beyond engineering limits. Extreme cold has interesting effects on electrons, most notably on batteries, and affected equipment should function as normal when back to normal temps.

Using the camera manufacturer's flashes in a high frame rate situation(weddings, events, etc.) can lead to catastrophic failure. Nikon has a thermistor built in to their higher end flashes to shut the flash down when it overheats. Unfortunately Canon hasn't done this and it is possible to push them to the point where either the main board fails or the xenon blows. Have an event guy who goes through 2-3 580EXes a year.

I try and steer these folks to a Quantum or some such. Actually cheaper in the long run, as well as cutting down on interrupted job panic.