The result of using extension tubes is that the distance from the back of the lens to the film surface is longer, which means you can take photographs at shorter distances to the subject. Extension tubes are thus commonly used for macro photography and sometimes for closeup portraits.
When using the camera's TTL metering system, no exposure compensation will be required (exposure compensation is required for handheld meters).
This version is fully compatible with Canon standard photo EF and TS-E lenses. Not recommended for EF-S lenses.
Extension Tube EF 25 is recommended for lenses with a focal lenght of 50mm and up.
Shortens focusing distance of lens