What the thread found

• Motor slippage on focus gear can be caused by insufficient torque between the motor and lens gear ring, where the motor needs to be pressed firmly onto the lens to maintain contact.
• The M-One motor mount can be flipped to position the mount on either side, changing whether the motor is pulled away from or pushed toward the lens when the attachment knob is tightened.
• Slippage can result from loose or flexing camera support rods that reduce overall mounting stability, which can be remedied using cable ties or a dogbone bracket to keep the motor secure against the lens.
• Motor potentiometer slippage occurs when the internal potentiometer becomes stiff and difficult to turn, causing it to slip relative to the output gear and progressively worsening focus marking errors during lens rotation.
• Transmitter potentiometer slippage happens when internal gears in the transmitter become loose, causing focus markings to change as the transmitter knob is turned.
• Calibration knob disturbance will shift all motor markings if the calibration adjustment knobs on the receiver are accidentally bumped.
• Potentiometer and transmitter internal issues require professional servicing by the equipment manufacturer, while mechanical mounting and calibration problems can typically be resolved on set.

Depends on

• The discussion centers on experiences with specific lens models and may not apply universally.
• Whether the M-One mount design flaw mentioned has been addressed in later production runs is uncertain.
• No detailed technical specifications or measurements provided for achieving proper motor torque.
• The effectiveness of temporary field solutions like cable ties versus permanent hardware modifications is not quantified.

Gear in this thread

BFD

Parts

Follow Focus

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