Wireless Lens Control, ARRI Style

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Designed to work seamlessly with the ARRI ALEXA line of cameras—the Plus, Plus 4:3, XT/SXT Plus, Studio, XT/SXT Studio, 65 and Mini—ARRI’s Wireless Compact Unit WCU-4 is a lightweight, handheld, remote-control system for lenses. No motor controller or extra power is required to use the WCU-4, as each camera possesses its own onboard wireless radio to easily take advantage of the unit’s compact, ergonomic housing. The WCU-4 works great with the Universal Motor Controller UMC-4 on the ALEXA, ALEXA XT, AMIRA and third-party camera systems utilizing professional lenses.

To say ARRI’s design is a remarkable feat is an understatement. The user-friendly unit’s infinite control with solid feedback enhances the collaborative process on set, easing extensive demands placed on camera assistants when using this most revolutionary remote focus to hit the market in close to a decade. The WCU-4 will work with any camera using any cinema lens, along with a number of ARRI camera control units. This includes the UMC-4, which can additionally control camera settings, as well as the Single Motor Controller SMC-1 (perfect for Steadicam or camera drones), the Controlled Lens Motor CLM-3 (a strong, fast lens motor to drive heavy, difficult-to-operate lenses), and the CLM-4 (a quiet lens motor to drive any standard lens). The UMC-4 also can be used with the Zoom Main Unit ZMU-3A, a handgrip zoom controller that looks and feels like an updated version of any number of standard industry zoom controllers.

Additionally, other ARRI tools can be paired with the WCU-4. For simple, single-axis motor operation, the Single Axis Unit SXU-1 is easily capable of controlling focus, iris or zoom. The Lens Data Encoder LDE-1 is also a valuable tool on set. For example, if a 1st AC insists on using a mechanical follow focus like the ARRI FF-4, and VFX still wants to know what’s happening with the focus during a shot, the LDE-1 can be used to capture the data of the marks being moved for focus. Keep in mind that if using ARRI motors, metadata capture is always available either in-camera (Plus module) or on an SD card in the UMC-4.

ARRI’s Electronic Control System can operate with up to two additional hand units with the UMC-4 in place. This setup gives filmmakers the option to use a separate controller for zoom and a third for focus or ƒ-stop. The WCU-4 also provides real-time, frame-accurate informational display on all three axes, including depth of field, even though each motor is working independently and being regulated by its own controller.

The WCU-4 offers full control over the camera to set frame rate, shutter angle, exposure index and more in an ergonomic design weighing only 1.7 pounds, making it one of the lightest 3-axis hand units on the market today.

When working with the Ultrasonic Distance Measure UDM-1, the focus motor can be set to continuously track the focus of a given object in a frame. This ostensibly creates an autofocus mode that can be overridden at anytime. The focus knob comes with adjustable friction that can be adjusted for personal preferences, its vibrating function indicating when preset focus marks have been hit. The WCU-4 comes with a large lens data display that reflects ambient light and remains clearly visible in direct sunlight, while its backlit focus knob and control buttons allow the unit to be used in darkness and low-light conditions.

All these tools offer filmmakers absolute control over their equipment in just about any situation. As a camera-interface, remote-control system, the WCU-4 is unparalleled in the field when working in conjunction with the ALEXA line of cameras. Functions such as Record start/stop, frame rate, shutter angle, ASA, color temperature, built-in ND filters, monitor output and false color can be viewed and adjusted easily. All ARRI lens tables are already available in the ALEXA Plus and UMC-4 firmware.

The WCU-4 is part of ARRI’s Electronic Control System; when the Universal Motor Controller UMC-4 is engaged, additional hand units can be used, giving filmmakers nearly infinite control.

In keeping with the continued trend to have effects in place on almost every shoot, the WCU-4 offers some highly useful tools for the VFX pipeline. Frame-accurate lens data records the status of the lens, including ƒ-stop, focus, lens size and time code, all stored as metadata along with the images during the recording process. This highly accurate data also allows lens mapping to pre-marked focus rings and focus tracking with the UDM-1. Metadata is captured with any ARRI LDS-enabled lens and can be downloaded with or without the WCU-4.

All this data allows for matching and creation of virtual lenses in postproduction, as well as seamless mapping and a more fluid workflow from production through VFX post. The WCU-4 is also designed for use as a broadcast-friendly unit, optional adapter modules providing direct compatibility and control of iris, focus and zoom on many broadcast and ENG Motor Controller EMC-1 lenses.

The WCU-4 is clearly the next step in modernizing camera and lens control. Several of the units are currently in the field, and Joe Segura, 1st AC, Local 600, recently used the system to great effect.

"I tested it when I worked on the feature film Dope," he explains. "The unit can be used on everything from rickshaws to cranes to Steadicam and handheld shots."

The WCU-4 is also compatible with Cinetape Plus monitors that can display ARRI Lens Data information, such as Transvideo, as well as Cmotion hand units.

For more information on ARRI products, visit arri.com.