Traveling to England.

We are going to visit our oldest son who is studying abroad in London.
Do I need to get a special charger and batteries for my XTi and 430 flash to convert to 220?

You just need a plug socket adaptor. London is a great place for shooting.

Not for the camera. The Canon charger is dual voltage. You will need a plug adapter though. Wall plugs there are different.

You may need a different charger for your AA cells though. Yours should say whether it's 120V or 100-240V somewhere on it. If it's not 100-240V you need to get either a new charger or a voltage converter for electronics along with the plug adapter.

Sterlingtek chargers work over here with a plug converter or plug into car cig lighter socket. As for the flash just use alkalines for your trip buy them here and then you'll keep your weight down.

I'm originally from Canada but have spent the last couple years in Scotland. To use your US stuff here you need, as said, an adapter that simply makes the connection into differently sized holes possible, and you must make sure that your appliances will support the higher voltage here. If your device has a plug that reads 120-220V (or higher) and 50-60Hz, then you are set. If it does include 220V or 50Hz then plugging it in here will probably damage it. I destroyed a power supply because I forgot to flip a switch that changed its expected input voltage and frequency... made one bright flash of light and became an expensive paperweight.

Whatever you do don't buy the converter at the airports. You'll pay 4 times as much.