Arri M40
The Arri M40 is an HMI, which stands for Hydrargyrum Medium- Arc Iodide. This fixture is a par style and has an 18-52 degree beam angle so relatively wide to very narrow. The M series has an updated reflector that increases output and creates an even beam removing the need for lenses. HMI bulbs range from 5000-7000 degrees kelvin.
Uses
HMI pars are usually used for hard sunlight for day interiors, or pushed through a frame of diffusion for a softer key. They can also be used for day exteriors as a backlight or fill, but a larger lamp may be required to compete with the sun.
Can also be used for night exteriors to mimic moonlight.
QC Process
Accessories
- It can also be used with a 2500w globe
- 15.5" speedring
- Medium quartz softbox
- Medium 40 deg fabric grid.
Troubleshooting
HMIs are inherently problematic and have some common issues.
- "Safety Loop Broken" This can show up on the ballast, a common fix is to make sure the safety glass is closed. It can also be because the head is off.
- Check all switches.
- The molded head feeder is often a point of failure, more so than other head feeders. You can test for a bad head feeder by plugging the light directly into the ballast and trying to strike it.
- Dimmers will not work unless the light is fully up to speed.
- The ballast should be placed in the shade to prevent overheating.
Substitutions
There are not many substitutions for this light, but the following lights could be used in place of one if they are willing to take a slightly different fixture.
- S360 Skypanel - As a soft source only
- Tungsten 10k or 20k - If they are on stage and want HMIs, they can swap with equivalent-output tungsten units.