Do your ellipsoidals not seem as “punchy” as they once were? Do you want to get significantly more output from your older fixtures? Perhaps a bench focus is in order…
Note: This is an older article, and bench focusing really only applies to conventional (Non-LED) ellipsoidals and a few other fixture. If you’re trying to breathe life into older fixtures, this will help you. If you have LED-based fixtures, this typically will not be available to you – it’s not necessary!
Perhaps your wash was once nice and even, but now is uneven and looks bad on camera. Did you change anything? Nope? Did the lighting gremlins come in and mess with you? Yep, they did!
Lighting Gremlins?..No! Bench Focus!
Okay, so there is no such thing as a lighting gremlin, but time, heat and usage do cause the focus of your lekos to shift. While this is happening, the internal alignment of the lamp in its reflector also gets out of whack, causing the symptoms mentioned above. The solution to this problem involves a bit of time and some elbow grease, but is totally worth it. It’s a process called bench focusing.
Bench focusing is the re-alignment of the ellipsoidal’s lamp, reflector and lens focus so that the light outputs the optimum brightness and evenness. This process is suggested every 2-5 years, depending on how much you move your lights around. Really, you just need to bench focus your lights when you notice it’s getting bad. Here’s how it goes:
Bench Focusing 101
The first thing you’re going to need to do is get a proper setup on the ground to do this properly. You want to be 50-75 feet away from a flat, perpendicular, single colored(preferably white-ish) wall. You need some sort of pipe and base or truss and base assembly to clamp the lights onto while you have them on.
Make sure you have your gloves and c-wrench. You’ll also need 1 circuit of wall power to plug in the lights. This guide uses the ETC Source Four, since it is common. If you use a different ellipsoidal, consult the manual for the specifics on lamp adjustment, though most of this guide will be the same for your lights.
First Things First
As you may have now figured out, you need to have all of your lights on the ground. You can do this one-at-a time if you’d like. With the house lights in the room off or very dim, hang the first light on your rig and turn it on. Open up all the shutters if they aren’t, and take the lens focus to sharp.
At this point, you should see an obvious hot spot somewhere near the center of the beam. If it is not centered, loosen the lower plastic screw on the rear of your fixture and move it to center, then tighten it. The next step is the move the lamp into the correct depth of the reflector.
To do this, you need to move your fingers back of the screw you just adjusted to the 2nd part of that piece of hardware. Move that hand-screw back and forth as you watch the light get brighter and darker. When the light is at it’s brightest over the whole beam, you’ll know you’re at the right place.
The first light will take the longest- but don’t be afraid. After 4-5 fixtures you’ll move through the rig quickly, as it becomes easy to get the fixtures at their brightest. Bench focusing is a great way to get a lot more output from your lighting system, all without spending a penny!