On the set, it is often necessary, or convenient, to have a holder that will allow the boom pole to be held steadily and securely in one position. Several devices are used for this purpose. The most common and cheapest is a simple fishing pole holder. These are a piece of round metal stock cleverly bent in a series of curves that support a pole by contacting it in two places, one on its top and the other on its bottom offset by a small distance. This system puts pressure on two points formed...