1800W HMI

Overview

On a film set, the term "1800W HMI" practically exclusively refers to the ARRI M18 – an open (lensless) daylight fixture from the ARRI M-Series with a lamp output of 1,800 watts. 1,800 watts is not a classic HMI standard wattage (common wattages are 575W, 1,200W, 2,500W, 4kW, 6kW, etc.); ARRI introduced this class together with the M18. The fixture combines the patented MAX Technology (lensless, reflector-based design) with a single-ended 1,800-watt HMI lamp.

A characteristic feature is the ratio of physical size to light output: the M18 is roughly the same size as a common 1,200-watt head, but according to ARRI, it delivers around 70% more light. MAX Technology dispenses with a front lens and combines the light characteristics of PAR and Fresnel in a single, focusable reflector.

Technical Specifications

Specific lux or illuminance values depend heavily on distance and focus setting and can be found in the respective ARRI photometric data sheet.

On-Set Usage

The crucial practical advantage of the 1800W HMI: According to ARRI, it can be operated from most household outlets worldwide. This makes the M18 the highest HMI output that can be drawn from a standard outlet without a separate generator or high-voltage connection – a reason why it is popular among commercial, documentary, and film crews as an all-rounder for daylight setups.

• Daylight Fill / Sun Replacement: Daylight-balanced source for interiors, window light, and supplementing weak sun.
• Power Efficiency: No generator logistics needed, ideal for small crews and locations without high-voltage power.
• Compatibility: Uses existing 575/1,200/1,800W cables and can also operate 1,200W lamps with the appropriate ballast.
• High-Speed Option: Flicker-free with a high-speed ballast for slow-motion shots at high frame rates.

Note: Fixtures are often rented "head only" – ballast, head cable, lamp, and barndoors may need to be booked separately depending on the supplier.