The Canon TL-28 Telephoto Converter increases magnification of distant objects by 1.7x. Depending on camera model adapters maybe required. This accessory lens screws onto the front of the camera's zoom lens.
This is the magnifying factor of a lens. Macro lenses will often be described by their “magnification factor”. A lens with a 1:1 magnification factor produces a projected image on the sensor which is the same as the subject.