How to Focus A Lighting Fixture
Focusing, no matter what kind of fixture you are working with, involves the same processes.
- Panning refers to shifting to the left or right.
- Tilting refers to shifting up and down.
- Locking a fixture means tightening all necessary bolts to keep it in place for the show.
The designer will ask you to put the Hot Spot or brightest part of the beam (which should be the center of the beam) where indicated. Typically the designer will stand in a certain spot and expect you to put the hot spot on their face.
- Sometimes a fixture has to be physically moved on the pipe it is hanging from in order to hit the right spot. This will mean loosening the C-clamp (which is why you brought a wrench) and sliding the fixture left or right. It may also mean Roostering the fixture, which means to shift the yoke of the fixture forward or back and tightening the c-clamp to keep it there.
- Flagging refers to waving a hand or something in front of the light so that the designer can see the difference.
- Shutters on a leko can give you cuts, creating a straight shadow to keep light off a certain areas or to shape the pool it makes. Remember when focusing that the reflector in a leko reverses the beam, so your left shutter makes a cut on the right and your top shutter makes a bottom cut.
[Make sure to put gobos in backwards too.]
Par-cans are the simplest lights to focus. Depending on the lens, many pars have a directionality to their beam. If a designer asks you to Spin the Bottle, they are asking you to turn the lens of the par to rotate the oval shape of the beam (up to down/ left to right).
Fresnels and Parnels have a knob that allows the beam to change from Flooded (wide) to Spotted (narrow).
Lekos have many other attributes.
The barrel at the end of the fixture (loosened and tightened by the barrel knob) moves a lens inside, which you can use to Sharpen or Soften the edge.
Lekos have 4 shutters, that allow you to Cut the light off of scenery or soft goods.
Lekos can also be equipped with Gobos, small metal discs with templates to shape the light. Breakups are gobos that create a general pattern to the light.
Iris kits can also be put into the fixture, that allow you to narrow the beam in a circular form in a variety of sizes.
Period maintenance of instruments should include Bench Focusing lekos. This involves throwing the lekos, one by one, at a flat white surface, and using the two knobs in the back of the instrument to move the hot spot more toward the center of the beam.