Vivitar's 1.4x Teleconverter for Canon can add another tool to your camera bag, at a very affordable price. This compact and lightweight 1.4x teleconverter multiplies the focal length of any compatible lens by 1.4--a 100mm lens with this teleconverter attached, for instance, would give you the view of a 140mm lens. This converter is not compatible with EF-S lenses. Autofocus will not work with lenses with a maximum aperture slower than f/4.5. The multi-coating on the converter reduces flare and ghosting, common problems with digital cameras. And, the minimum focusing distance is unchanged. This teleconverter comes with a lifetime warranty.
For Canon cameras and lenses with an EF mount--not compatible with EF-S lenses