What the thread found

• When a Preston focus controller is mounted to a donkey box, the additional mass is added above the gimbal and requires compensating adjustments to camera and monitor placement for balance.
• Components mounted above the gimbal should be positioned as close as possible to the center post to minimize balance disruption.
• Camera accessories should be mounted close to the camera body and near the post.
• Static balance is typically achieved by positioning the camera approximately one inch behind the center of gravity initially.
• Dynamic balance is often reached when the center of gravity of the complete camera setup falls approximately one to two inches behind the center post.
• With heavier camera bodies and large cinema lenses, it may be necessary to position the camera at the center of the post initially to allow sufficient room for moving batteries backward to achieve dynamic balance.
• Achieving proper balance requires individualized adjustment since every rig configuration is different and there is no universal formula.

Depends on

• The specific balancing distances mentioned are guidelines rather than fixed rules and may vary based on the particular components used.
• The method of spinning test balancing is presented without detailed explanation of procedure.
• Discussion focuses primarily on professional cinema camera bodies and large-format lenses; applicability to other camera systems is unclear.
• No information provided about the specific Preston MDR model mentioned in the title.

Gear in this thread

MDR

Parts

Donkey Box

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