Canon Close-up lenses are for quick and easy close-up photography. The close-up lens is screwed on to the front of a lens like a filter.
Close-up lens 500D has two achromatic elements to correct chromatic aberrations. They do not degrade the high optical performance of EF lenses.
The 500D is geared for lenses with a focal length anywhere from 70 to 300mm.
Double-element accessory attaches to front of lens, changes closest focusing distance from infinity to 500mm (approx. 19.7") from front of lens.