Add the 1.6X Tele-Converter to the front of your 16X zoom to shift its focal range in the telephoto direction. The perfect tool when it's inconvenient, dangerous, or even impossible to move as close to the subject as you'd like. The 1.6X Tele-Converter alters your zoom's focal length range from 5.5-88mm to 56-140mm - with no appreciable light loss. Note that the Tele-Converter offers partial zooming: focal lengths of less than 55mm exhibit vignetting.
The Tele-Converter is specially effective in "run-and-gun" shooting situations because it attaches more quickly than rear-mount tele-extenders, and doesn't require exposure of the XL1's delicate electronics.
Need even more telephoto range? Add the Century 1.6X Tele-Converter to the front of your lens and Canon's 1.6X Tele-Extender to the rear, for the widest possible range -17.6-225mm, with no vignetting.