1. Metal gobos are considered “consumables,” meaning they are expected to “burn out” after a given amount of time and usage. The metal becomes fatigued to the heat of the lighting instrument.
Each gobo has a different expected life span, influenced by the amount of supporting metal, the detail of etching, and the alignment of the lamp in the fixture.
One way to extend the life of a gobo is to allow the lighting instrument that it is inserted into to cool to room temperature before removing the gobo and its holder. This allows the metal to regain some of its original tensile strength.
This will not make gobos last forever but may help increase their usefulness by several burn hours.
2. When trying to make cloud effects with gobos, try a couple approaches:
Start with the gobo extremely unfocused and slowly begin to “crispen” the focus by adjusting the fixture barrel. You will be amazed at how much more realistic cloud gobos can seem when they are extremely misfocused. Also, try using different degree spreads of instruments from extreme angles to gain more depth and variety of size of image.
When using cloud gobos, be aware that you are imitating nature. The audience has an expectation. Be accurate by not mixing “types” of clouds that would not normally be in the sky together, such as cumulus and cirrus; nature generally does one or the other. Also, pay attention to any textual reference to what sort of weather might be occurring. A rainstorm does not generally come out of cirrus clouds. Remember—audiences are smart.
When you are trying to cover large areas with breakups or using more than one gobo to cover a cyc with clouds, use more than one design of gobo. This helps add depth and interest to a breakup wash on a stage floor. With cloud gobos, hold several designs up to each other and look through them towards a steady light source. Notice that they are designed to “nestle” into each other, filling the negative and positive space of each other. Using these in a layered focused with independent control of each feature allows you to vary which is the predominate pattern in the sky, adding to the illusion of the clouds changing shape (as you vary the intensity of each independent fixture’s dimmer), just as they do in nature.
3. Consider using “burned” gobos for as long as possible. Some of the designs such as clouds, leaves, and breakups become more interesting as they change shape through burnout.