Bench focusing a Source Four is a necessary part of your regular maintenance on Source Four fixtures. It properly aligns the lamp with the reflector to ensure you get a nice flat field that produces optimal lumen output, and prevents gels from burning through too quickly.
Basic Bench Focusing Steps
- Create a hard edge by adjusting the barrel
- Center the hot spot by rotating the outer knob clockwise until the knob is tight. Loosen the knob until the hot spot is centered in the field
- Flatten the field by rotating the inner knob. A hot spot or hole appears in the field if it is not aligned correctly.
You can also watch ETC's Bobblehead Fred Short on Bench Focusing a Source Four below, and use the following images to reference knob placement and field alignment.