Canon EF Converter for 50mm Macro Lens optional accessory is designed to work strictly with the EF 50mm f/2.5 Compact Macro lens. Unlike typical life-size adapters, the Life Size Canon EF Converter for 50mm Macro Lens actually has optics that are optimized for high magnification when combined with the 50mm macro lens. Magnifications of Canon EF Converter for 50mm Macro Lens from 0.26x (approx. 1/4 life-size) to 1.0x (true life size) is possible, at increased working distances.