In my opinion, the converters use when budgets are tight, the main reason for buying this lens. A favorable Tele, which is suitable converter, not there from Canon. The lens works with 1.4 or 1.5-converters (for me Kenko) knotless together, the picture quality is still acceptable even at upmarket requirements with some softwareseitigem sharpening at telephoto. Macro photography with close-up lenses are, however, in this lens hardly in it, if you still want to use the Auto Focus. This is overwhelmed regularly. Better select a tripod and manual focusing. The price / performance ratio is excellent for me in total this metal mount lens. So far me the lack of USM and image stabilizer are not significantly disturbed, it scores the lens with relatively low weight and good handling. It can be sometimes easily fits in your pocket. Who does not require a converter, should the EF-S 55-250 grab (my personal favorite Tele Canon). This provides for a few euros more the much better picture quality and greater sharpness including stability at the telephoto end, for significantly more money there's the 70-300 USM a comparable focal length with image stabilizer and also significantly better Tele sharpness, but also significantly more weight and bulkiness. Professionals access anyway to 70-200, but that is nochmel ne other price class.
