A method and system that combines efficient caching and buffering to provide a network file system, that may utilize data stored in one or more compressed image files of sequentially arranged byte stream data. Test signal data is used to assist the operator in insuring the levels are set to the intended display characteristics in the event that factors such as creative lighting or applied effects affect the desired look of the scene. The computing node is responsible for managing the security based on a node security profile interpreted by a node security program executed in the computing node. The filter element includes at least one barrier and a plurality of apertures positioned to cause inflation gas from the combustion chamber to travel from the opening in the combustion chamber cap to the exit port along a tortuous path including at least one debris pocket and at least one impact region. The depth of field of the detector is small and the focal plane is no further from the surface of the patterning device than two times the depth of field.