Blackmagic Design Camera URSA EVF 1/4 Thumbscrew

Blackmagic Design Camera URSA EVF 1/4 Thumbscrew

The Blackmagic Design Camera URSA EVF 1/4 Thumbscrew is a specialized, precision-engineered spare part designed for the Blackmagic URSA Viewfinder. This specific screw is used to secure the viewfinder to the URSA Mini Shoulder Kit or the camera's top handle assembly.

Technical Design and Specifications

Unlike generic hardware store screws, this thumbscrew is custom-milled to meet the specific clearance and torque requirements of the URSA rigging system.

• Thread Type: Standard 1/4"-20 thread, which is the industry standard for camera mounting hardware.

• Captive Design: The screw features a "waisted" or "relieved" shank. This allows it to remain attached to the viewfinder's mounting bracket even when loosened, preventing the screw from falling out and getting lost during camera transitions.

• Knurled Grip: The head of the screw is oversized and features deep knurling (textured ridges), allowing camera operators to tighten or loosen the viewfinder by hand without needing a screwdriver or hex key.

Primary Functions

• Angle Adjustment: It serves as the primary pivot lock. By loosening the screw, the operator can slide the EVF forward or backward along its mounting rail or tilt it to the desired viewing angle.

• Secure Locking: When tightened, it provides the high clamping force necessary to ensure the viewfinder remains rock-solid, even when the camera is being moved aggressively on a shoulder rig.

Compatibility

This spare part is essential for the following hardware:

• Blackmagic URSA Viewfinder: The high-resolution OLED eyepiece used across the URSA and URSA Mini lines.

• URSA Mini Shoulder Kit: Specifically the top handle and rail mount section where the EVF attaches.

• Blackmagic URSA Broadcast: When utilized with the professional eyepiece.

Operational Insight

This thumbscrew is a frequent "wear and tear" item for rental houses and high-volume production companies. Because it is handled constantly for ergonomic adjustments, the knurling can eventually wear down, or the thread can become cross-threaded if forced.

Because it is a captive screw, replacing it typically requires removing a small C-clip or retention plate on the viewfinder mount. Once the old screw is removed, the new spare is threaded through and secured, ensuring the EVF is once again field-ready.

Tip: If you are building a "Crash Kit" for a long-distance shoot, this is one of the most important small parts to include. Losing the EVF thumbscrew on location can effectively render the electronic viewfinder unusable, as there is no other way to safely secure the heavy OLED eyepiece to the camera rail.