Comments about Ikelite Ikelite Underwater Camera Housing for Canon EOS Rebel XSi (450-D) Digital SLR Camera:

Purchased this housing when I upgraded from a compact digital to the Rebel XSi for underwater photography. The system is necessarily more complex in order to accommodate the many features of the DSLR system, such as interchangeable lenses and eTTL strobe control. But it is not difficult to learn both the loading and assembly steps as well as the actual operation of the camera underwater.

I do recommend spending plenty of time on dry land learning the placement and function of all the controls, even though you will only use two or three of them (shutter, focus/zoom and maybe aperture control) while underwater.

The attachment of the port to the housing does not seem like it would be waterproof, but it works fine. I've had the camera to 126 feet with no issues at all.

I highly recommend if you're ready to take your XSi for a dunk.