How often does the "lightbulb" in the 550 EX break

[DocFrankenstein]

Just wondering... What "lamp" is used in the 550 EX and how many flashes can you get before it dies?

[Jon]

It's a (probably custom) Xenon discharge tube. Frankly, I think you're more likely to blow one of the capacitors than the tube barring manufacturing defects.

[DocFrankenstein]

So basically it's unlimited shooting, right?

[Jon]

As far as the flash tube, yes. It's more like a fluorescent light than an incandescent. The most likely parts to die are outside the tube.

[robertwgross]

The flash tube, itself, is not the normal cause for failure. Apparently you can cause premature death of the flash tube by firing it too often and too quickly, and the book mentions that (keyword: stroboscopic).

More typically, a flash unit fails because of a failed main capacitor, other electronic components, and user controls. A common failure area is in the connection to the camera, especially in the hot shoe "foot".

---Bob Gross---