The Focus/Iris (aka Single Channel) wireless hand control provides the reliability and robustness you expect from Preston in a compact, lightweight package. It can be used with the rest of the FI+Z system to take over the Iris or Focus function from the HU4, selectable with a toggle switch on the front panel of the unit.

The F/I features a bright LED bar graph display of lens position. End limits can be set with the touch of a button and are shown as illuminated bars. A tri-color LED is used to indicate wireless signal strength, along with red LED indicators for wireless channel, battery voltage status, and camera run/stop.

A soft urethane grip makes for comfortable all-day operation. Marking discs slide over the knob onto an index pin, so the user can know the current lens position without being near the camera. Power is provided by a standard FM-50 Li-Ion battery, allowing for approximately 8 hours of operation.