The Canon Speedlite 550Ex is a high-output flash unit featuring E-TTL (evaluate through the lens) autoflash control. Additionally, the flash unit can be used as an on-camera flash, or as a master or slave unit in a wireless system. The 550Ex is able to obtain natural looking flash by balancing the flash output and the existing light. There are several tips and tricks Speedlite users can implement to optimize the unit's functionality.
Quick Flash
The 550Ex uses a quick-flash feature. With the feature, users can fire a flash even before the flash is fully charged. When the pilot lamp (on the right side of the flash) turns yellow, a quick flash can be fired. The Guide Number for a quick flash is between 1/2 to 1/16 of a normal flash. A quick flash cannot be fired when the camera is set to continuous shooting, when Flash Exposure Bracketing (FEB) is used, or when the manual flash mode is in use.
Automatic Zoom
The Speedlite's flash head can automatically zoom to provide the coverage needed for the camera lens' focal length. The 550Ex provides adequate coverage for 24mm to 105mm focal lengths. When the camera's zoom lens is zoomed, the flash head will also zoom to suit the lens focal length. The flash head's zoom can be zoomed automatically as well. Press the "Zoom" button once to turn on automatic zoom. Press the camera's shutter button halfway to turn on allow the flash head to zoom.
Film Speed and Flash Mode
The film speed is set automatically according to the film speed that is set within the camera. 550Ex owners can change the flash mode to a variety of settings. Press the "Mode" button (to the left of the "Zoom" button) to change the flash mode to either "E-TTL Autoflash," " Manual Flash," or "Stroboscopic Flash." The LCD panel will display the currently selected flash mode.
AF-Assist Beam and Default Settings
When the Speedlite is in areas of low light or low contrast, the unit will automatically emit the AF-assist beam to assist in autofocusing. The AF-assist beam is compatible with the AF in all EOS cameras. The beam is especially effective with 28 mm (and longer) lenses. The 330Ex can also revert to its default factory settings when connected to a EOS camera equipped with a "Clear" button. Pressing the clear button on the camera will reset the Speedlite's settings to its default settings (except for custom functions).
Tags: flash head, flash mode, quick flash, change flash, change flash mode, film speed