Flash External Metering

The Speedlite's built-in external metering sensor measures the flash light reflected from the subject in real time and automatically stops the flash firing when the standard exposure is reached.

"Auto external flash metering" can be used with the EOS DIGITAL cameras released in and after 2007. "Manual external flash metering" can be used with all EOS cameras.

Ext.A: Auto External Flash Metering

You can shoot in fully automatic flash mode. The flash output is automatically adjusted according to the ISO speed and aperture set on the camera.

  1. Select MODE with the joystick.

  2. Set the flash mode to Ext.A.

    • Press the joystick vertically or horizontally or turn Select dial to select Ext.A, then push the joystick straight in.
    • When you press the camera's shutter button halfway, the effective flash range (1) is displayed.

Note

  • When Ext.A is set, you can use flash exposure compensation () and FEB ().

Ext.M: Manual External Flash Metering

You can manually set the Speedlite with the ISO speed and aperture set on the camera. The flash output is automatically adjusted according to the ISO speed and aperture that you set.

  1. Select MODE with the joystick.

  2. Set the flash mode to Ext.M.

    • Press the joystick vertically or horizontally or turn Select dial to select Ext.M, then push the joystick straight in.

  3. Set the same ISO speed as on the camera.

    • Push the joystick straight in.
    • Press the joystick vertically or horizontally or turn Select dial to select item (1), then push the joystick straight in.
    • Push the joystick to the left or right or turn Select dial to set the ISO speed, then push the joystick vertically.
    • The ISO speed can be set within a range of ISO 25 to ISO 819200, in 1/3 increments.

  4. Set the same aperture as on the camera.

    • Press the joystick vertically or horizontally or turn Select dial to select item (2), then push the joystick straight in.
    • Push the joystick to the left or right or turn Select dial to set the aperture value, then push the joystick vertically.
    • The effective flash range corresponding to the preset ISO speed and aperture value is displayed.

Note

  • When Ext.M is set, you can use a commercially available sync cord to connect the sync terminals of the camera and the flash and then shoot with the flash separated from the camera.
  • Even if you connect a different Speedlite to the Speedlite's sync terminal with a sync cord, it will not fire.