Setting the aperture

Still photography

Use the camera body to control the aperture (except during movie capture).

To control the aperture in 'M' mode the rear quick dial (if your camera has one) must first be turned on.

turn on the rear quick dial

Movie recording

5D Mark II 

If your camera body is set to 'M' exposure mode, the following instructions may NOT apply. Follow Canon's instructions instead.

If your camera body is not set to 'M' exposure mode, your camera always automatically chooses ISO and shutter speed. By default, the camera automatically choose the aperture as well, but you may manually control the aperture using the aperture ring of the lens.

To control the aperture for movie recording,

  1. Put your camera in LiveView mode by pressing the LiveView/Print button.
  2. Set the LiveView display to "Exposure Simulation". (Press MENU. Choose "LiveView/Movie func. set." from the middle settings tab. Choose "LV func. setting".)
  3. Rotate the lens' aperture ring. You are now in LiveView Aperture Control mode.
  4. You may now begin movie recording by pressing the SET button and use the aperture ring to directly set the desired aperture.

To exit from LiveView Aperture Control mode, either

  1. use "Quick AF" in LiveView (not during movie recording), or
  2. press the DoF preview button, and release it (not during movie recording), or
  3. exit LiveView mode.

Note: the lens remains stopped down after you stop movie recording. Do one of the above if you need to reset the aperture diaphragm to wide open.

Rebel T1i/EOS 500D

  1. Cover the lens with a lens cap first. (This is because the lens' aperture is controlled by either the Canon camera body or the Conurus firmware, but not both. Covering the lens with a lens cap will force the camera body to use the maximum aperture, thereby relinquishing control of the lens' aperture.)
  2. Turn the mode dial of the camera body to 'movie shooting'.
  3. Turn the aperture ring of the lens. (Now, Conurus firmware takes over control of the lens' aperture.)
  4. Remove lens cap.
  5. Use the lens' aperture ring to set the desired aperture.

Press red movie shooting button on the back of the camera to begin movie capture.

To exit from Movie Aperture Control mode, either

  1. use "Quick AF" (select quick AF mode and press the * button), or
  2. turn the mode dial to exit movie shooting.

General Information 

With a variable-aperture zoom lens, if you zoom after choosing an aperture, the taking aperture varies as a variable zoom would. For example, if you choose f/4 with a Vario-Sonnar 24-85/3.5-4.5 lens at 24mm, and you zoom to 85mm, your taking aperture is now f/5.6. This behaviour is the same as a manual focus zoom lens. This design choice is made so that, although a variable-aperture zoom's aperture changes as you zoom, the aperture diaphragm does not change so as not to produce an obtrusive click noise or cause a sudden exposure change in the footage.

The minimum firmware version required for the LiveView Aperture Control feature is v3.00 (2009/05 or after). Existing customers may send their lenses in for a firmware update to the latest version for a nominal shipping charge. You may find out the firmware version of your lens by entering the serial number or tracking number here.

Please enter the serial number or post-office tracking number of your lens: