FAQ: I changed my monitor / physical configuration - How do I update the Host PC?

[Sam]

If you change the display monitor or its physical position, you must update the screen configuration settings on the Host PC. This ensures the accuracy of the event data (saccades, fixations, etc...). Failing to update these settings will result in incorrect calculations for metrics such as pixels-per-degree resolution, saccade amplitude, and velocity. However, the raw positional gaze data itself remains valid as long as you have a valid calibration for that session.

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EyeLink 1000 Plus & EyeLink Portable Duo

• From the Host Software, press CTRL+ALT+Q to open the File Manager.
  
• In the File Manager, click the gear icon in the top-left corner or press CTRL+ALT+C to access the Configuration Screen.
  
     
• In the Configuration Screen, select the screen icon to open the screen settings.
  
     
• Follow the on-screen instructions to enter the correct values for:
  • Screen Size
    
  • Display Resolution
    
  • Eye-to-Screen Distance
    
  • Camera-to-Screen Distance
    
• Once complete, click the Save button and then click the EyeLink logo icon to restart the host software.
  

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EyeLink II & EyeLink 1000

• From the Host Software, press CTRL+ALT+Q to exit the application and enter the DOS environment.
  
• In DOS, navigate to the C:\ELCL\EXE directory by executing the following command:
  
  Code:

  cd c:\elcl\exe
• type the following command to open the configuration file in a text editor:
  
  Code:

  edit physical.ini
• In the text editor, modify the values for the following commands to match your physical setup:
  • screen_phys_coords
    
  • screen_pixel_coords
    
  • screen_distance
    
  • marker_phys_coords
    Note: The marker_phys_coords command only applies to EyeLink II systems.
    
  • *If using the EyeLink 1000 in remote mode mode, see additional notes below*
    
• Save the file and exit the text editor.
  
• Restart the Host Software for the changes to take effect.
  

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Configuration for Remote Mode (EyeLink 1000)
When using the EyeLink 1000 in Remote Mode, you must specify the camera's physical position relative to the monitor. This is done by adding the remote_camera_position command to the FINAL.INI file located in the C:\ELCL\EXE directory.

You'll need to modify the dz parameter within this command to reflect the distance between the camera and the calibration plane (i.e., the monitor screen). This value must be entered in millimeters and should be negative, assuming the camera is placed in front of the screen. For example, a measured camera-to-screen distance of 25 cm should be entered as -250.

• From the Host Software, press CTRL+ALT+Q to exit the application and enter the DOS environment.
  
• In DOS, navigate to the correct directory by typing:
  
  Code:

  cd c:\elcl\exe
• type the following command to open the configuration file in a text editor:
  
  Code:

  edit final.ini
• Add the command below to the file. Be sure to modify the final parameter (dz) to match your measured camera-to-screen distance in negative millimeters.
  
  Code:

  ## remote_camera_position <rh> <rv> <dx> <dy> <dz>
;; <rh>: rotation of camera (yaw)
;; <rv>: tilt of camera (pitch)
;; <dx>: horizontal offset in camera coordinates
;; <dy>: vertical offset in camera coordinates
;; <dz>: distance from screen to camera lens (mm)
remote_camera_position 10 17 -80 60 -90
• Save the file and exit the text editor.
  
• Restart the Host Software for the changes to take effect.