Internal Extender Switch * There are times when an error message will be displayed and shooting operation is prevented. If this occurs, please turn the camera OFF and then ON.
EF400mm f/5.6L USM Other professional features are: a built-in lens hood with locking mechanism, dual manual focusing rings, a removable ring-type tripod mount, full-time manual focusing, and focus range selector for 3.5m to infinity or 8.5m to infinity. Extenders EF1.4 X and EF2 X can be used with manual focusing.
Tips on Using the Image Stabilizer Set the STABILIZER switch to OFF when you are taking pictures using the Bulb setting (long exposures). If the STABILIZER switch is set to ON, the image stabilizer function may introduce errors .