bench focus

Also known as "lamp optimization" or "tuning," the act of aligning the lamp so that its filament is at the optimal focus point in the reflector. Rarely done on a work bench--ideally the fixture is hung at a comfortable height perpendicular to a white wall or other flat surface. One possibility, in a counterweight house, is to fly in the 1st electric to a trim of about +5', and focus the fixture onto the cyc. Each brand of fixture has slightly different adjustments. While most agree that the procedure should be done every time a new lamp is installed, including on moving lights, often this is impractical.

Directions for an ETC SourceFour ERS: http://www.etcconnect.com/docs/docs_downloads/miscdocs/S4_Focus_Tuning.pdf

See also this thread: http://www.controlbooth.com/forums/lighting/257-technique-bench-focusing-360qs.html.