Arrimax 18K

Overview

The ARRIMAX 18/12 (often shortened to "Arrimax 18K") is an HMI daylight fixture from Munich-based manufacturer ARRI and part of the M-Series. Its most significant feature is its lens-less design: instead of the diffusion lenses common in traditional PAR fixtures, the ARRIMAX utilizes a faceted parabolic reflector ("MAX Technology"), which allows the light's characteristics to be adjusted solely by moving the lamp. This results in a very clean, sharply defined shadow and a uniform beam across the entire adjustment range, without the visible multiple shadows typically produced by lens packages.

The fixture accepts both 18kW and 12kW lamps on the same lampholder, hence the designation "18/12". ARRI markets the unit as one of the most powerful HMI fixtures on the market; the original ARRIMAX system was awarded a Technical Oscar (Scientific and Engineering Award) by the Academy.

Technical Specifications

Note: Manufacturer specifications and sales data sheets may vary slightly (e.g., reflector diameter and weight) depending on configuration and accessories.

On-Set Usage

The ARRIMAX 18/12 is typically used as a key or backlight for large setups, such as for brightening exterior daylight scenes, as an artificial sun, for backlighting windows, or for illuminating long distances. Due to its high power output, it requires a suitable electronic HMI ballast and an appropriate power supply; a modern ballast provides regulated, flicker-free operation even for high-speed shooting.

Because of its weight and size, the ARRIMAX falls into the heavy lighting class and is usually positioned on robust stands, combo stands, or via crane/condor. Rigging clearly falls within the responsibilities of the gaffer and grips/lighting technicians. The lens-less beam makes it particularly popular when a hard light cone, precisely controllable with flags and cutters, is required.