Using macOS Sierra with Canon EOS-1D X Mark II, EOS 80D and EOS 5D Mark IV

This FAQ entry includes information to work-round possible issues when connecting certain Canon cameras on macOS Sierra with Reikan FoCal. This is a temporary solution for FoCal 2.4, the final fix will happen in an upcoming release (waiting on Canon libraries update).

Most Canon cameras will work without any special tricks, we do believe there's an underlying issue connecting specific cameras EOS-1D X Mark II, EOS 80D and EOS 5D Mark IV and this FAQ should help get you up and running.


Any of the following error messages shown below are a symptom of the connection problem and this FAQ should help resolve the issue.


1. Quit EOS Utility Launcher

If you have NOT installed Canon EOS Utility, you can skip this step.

By default, if you install the Canon utilities (supplied with your camera or via Canon support site), an application called EOS Utility Launcher is installed and active all the time your computer is running. This is shown by an icon on the top right of the screen, to quit this application, right click on the icon and choose Quit from the menu.

2. Launch macOS Photos

When the macOS Photos application is running, it manages the connection to the camera in a way which allows FoCal to communicate with the camera.

To launch the app, click on the Photos icon as shown below and the Photos app will start up.

You don’t need to do anything within the Photos app, so you can just minimise the application by clicking the green “-” button on the title bar. As long as there’s a black dot shown underneath the Photos icon on the dock at the bottom of the screen you’re all set.

3. Connect the Camera

Connect the camera via USB cable and ensure camera is turned on.

4. Turn on FoCal and Press Connect

Now the Photos app is running you can connect and disconnect FoCal as normal.


  1. If you have installed the Canon software for Mac and have the EOS Utility Launcher application running, you should quit this.
  2. Launch the macOS Photos application and ensure this is running while using FoCal (you can minimise the Photos app).
  3. Connect camera via USB and power on camera as normal.
  4. Start FoCal and hit Connect, when the Photos app is running FoCal will work as normal.