What the thread found

• The Alexa camera body has an uneven bottom surface that prevents direct mounting of dovetail plates, requiring an intermediate adapter plate.
• A custom adapter plate can provide a flat mounting surface with standard Arri hole spacing, allowing older Arri dovetail plates to work with Alexa cameras.
• The adapter extends fore-aft range of dovetail plates by approximately 1.5 inches since it can be mounted in either direction.
• Using a custom adapter instead of Arri's quick-release plate saves approximately 2 pounds of weight.
• The adapter shortens the lens-to-gimbal distance by roughly 1 inch compared to Arri quick-release or bridge plates.
• The custom adapter avoids the side offset problem that occurs when using Arri's BPA-1 adapter with older bridge plates.
• With Alexa's newer BP12 bridge plate designed for the camera, an adapter plate is not necessary.
• Material is aluminum with weight of approximately 100 grams.

Depends on

• The adapter is only needed when using older bridge plates with Alexa; the newer BP12 bridge plate designed for Alexa eliminates this requirement.
• The adapter's necessity depends on whether rental houses supply the required bridge plate or quick-release configuration.
• Actual production status and availability were uncertain at the time of discussion.

Parts

Dovetail Plate

Same gear or parts

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