For some stage performances, fires, or the appearance of fires, are needed. Whether the illusion is of campfires, wizards shooting balls of fire from their hands or entire cities burning, solutions of varying difficulty exist for every stage fire need.
In some cases, real fire can be used. Pyrotechnic equipment, while impressive appearing, can be dangerous. Beware of legal concerns, including transportation, possession and storage, and licenses and permits to use. State and local authorities should be consulted on the specifics far in advance of any performance, as should representatives of the venue. This solution is better left to professional theater companies.
Gels, shaded transparencies designed to go in front of theater lighting, are used to provide the colored lighting effects of fires. Gobos (short for "goes before optics") are items with shaped holes that can be placed over lighting sources to create patterns. Flickering lighting can be created by using a mixture of red, orange and amber gels, with an appropriate gobo. Depending on the lighting system used, the gels and gobos can be set to rotate, and some computerized systems can be set to randomize gel color changes, making for a more realistic flickering effect.
The most common way to create visible flames is using silk, or another light material. Colored silk can be cut, either in strips or in a long cloth, to resemble fingers of flame. Once these are anchored, a fan is placed underneath them. When the fan is on, the strips are wave about in the air. By using colored lighting, the illusion of flame can be enhanced.
Certain situations may call for smoke to accompany fire. Luckily, smoke is a relatively easy effect to pull off. Smoke projectors are relatively inexpensive, and dry ice can be used with care to simulate smoke effects as well.