How to Make a Gobo Projectorby Darrin Meyer
A Gobo is a specific lighting effect created when a small template containing a logo, message or other image is lit by a lamp and projected to appear larger on a screen or other surface to which the projector is aimed. Gobo projectors are commonly used for various types of events, and though they can be purchased or rented from professional lighting suppliers, you can also create the projector and the Gobos themselves, provided you have the proper materials and skill set.
Obtain a light source for the projector, preferably an electric, LED or metal halide/gas discharge lamp that matches the diameter of the cylinder you will use for the projector's main housing. The light source should also come with a fan or other cooling system, as the act of generating light also generates a great deal of heat, especially during long periods of usage.
Cut slits in the cylinder at roughly the halfway point where the Gobo will be inserted using a metal-cutting tool or kit. Also, cut or drill matching holes on the sides of the cylinder for the locking knobs to be screwed in, and cut additional slits in the section where the light source will be to create ventilation.
Install the condensing lens within the lower half of the cylinder, using a round bracket to secure it into place. Also install a flat plane of heat-absorbing glass between the condensing lens and the slot where the Gobos will be placed, to prevent the Gobo from overheating.
Install an adjustable focusing lens on the end of the cylinder. With this type of lens, you can bring the image into focus when projecting it onto surfaces at varying distances.
Insert the light source housing into the cylinder and secure the light source in place. Attach the cylinder to the base, screwing in the locking knobs on each side.
Create the Gobo by tracing the image, text or design onto the surface of the brass or steel plate and cutting the design image out of the plate using the metal-cutting kit. Insert the Gobo into the designated slot of the projector cylinder.
Plug in the light source's AC power cord to a nearby outlet and aim the projector at the wall or other surface you wish to display it on. Adjust the focusing lens if necessary and loosen the locking knobs to raise or lower the angle of the projector.
- The Gobos themselves can be circular and secured in a square or rectangular frame for installation or square/rectangular shaped and just large enough to fit into the cylinder without a holder.