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ARRI cforce motors

Overview

Compatible models:

  • ARRI cforce mini
  • ARRI cforce mini RF
  • ARRI cforce plus

Wiring

  • up to 3 motors on the CAN bus
  • the last motor takes power from 2nd port
  • the first motor connects the LBUS CAN-L and CAN-H to the USB dongle
  • the USB dongle plugs in any USB port of the RIO

optional:

  • link RCP/RIO through ethernet, wifi, 4G, etc.
  • add blackmagic handles (so iris is done on RCP and zoom/focus with the blackmagic handles)

On the USB dongle, should be wired:

  • CAN-L
  • CAN-H

Setup

On an existing camera, scroll to Lens section:

  • Model : select ARRI - cforce
  • Interface : select your USB dongle (in my case USB:1, which means USB on port 1)

By default:

  • iris + zoom + focus are controlled
  • iris 1.6 to 32 with torque 2, direction left
  • zoom torque 2, direction left
  • focus torque 2, direction left

You can alter the configuration, especially to adapt the iris range:

  • top right of the panel, click on ...
  • activate "advanced mode"
  • come back to your lens setup, new Advanced field
  • text, zoom|iris|focus config serparated by , (each block should be fully configured: range if applicable, function, torque and direction). If you just configure iris, default focus and default zoom are still applied.
  • formats:
    • iris : IRIS_MIN:IRIS_MAX:iris:IRIS_TORQUE:IRIS_DIRECTION
      • IRIS_MIN is the minimum iris value
      • IRIS_MAX is the maxium iris value
      • IRIS_TORQUE is the torque of the iris motor (1, 2, 3 or 4)
      • IRIS_DIRECTION is the direction of the iris motor (left or right)
    • zoom: zoom:ZOOM_TORQUE:ZOOM_DIRECTION
      • ZOOM_TORQUE is the torque of the zoom motor (1, 2, 3 or 4)
      • ZOOM_DIRECTION is the direction of the zoom motor
    • focus: focus:FOCUS_TORQUE:ZOOM_DIRECTION
      • FOCUS_TORQUE is the torque of the focus motor (1, 2, 3 or 4)
      • FOCUS_DIRECTION is the direction of the focus motor (left or right)
    • examples:
      • 1.6:32:iris:2:left : iris from 2 to 8, torque is 2, direction is left
      • 2:32:iris:2:right : iris from 2 to 32, torque is 2, direction is right
      • 1.6:32:iris:2:left,zoom:4:right : iris from 1.6 to 32, left and torque is 2. Zoom with torque 4 and direction is right. No focus.
      • 1.6:32:iris:2:left,zoom:4:right,focus:2:left : iris, zoom and focus with torque 2 and direction left

If everything is properly configured and wired, the lens block should appear green:

info

Here the camera head is "Not controlled", so I just have read/write of iris/zoom/focus. But I could combine it with any camera control.

Calibration

You can run the motor calibration from the RCP:

This menu is available in MENU > LENS > LENS > ACTION, click on Calibrate