What the thread found

• The Bartech M-One motor may show a slight delay in focus mark alignment when reversing direction of the focus knob, with marks appearing slightly off in one direction compared to the other.
• A deliberate software delay is built into the system to prevent hunting behavior when changing direction, and marks should realign correctly once this delay period passes.
• Possible causes for focus misalignment include flexing in matte box rods that shift motor position, insufficient torque setting on the BDR unit, or backlash in the transmitter gears.
• Rod flexing and torque settings can be adjusted in the field, while gear backlash requires sending the unit to the manufacturer for repair.

Depends on

• The issue was described as a fraction of a mark difference and did not concern experienced focus pullers on set.
• Testing was performed with an M26VE motor paired with a BDR, which may differ from the original M-One configuration mentioned.
• No definitive root cause was established for the reported misalignment, and the user did not confirm whether the issue persisted after consultation.

Parts

Follow Focus

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