Field recording is the term used for any recording produced outside of a recording studio. Field recordings can be either of two varieties. Field recording of natural sounds, also called Phonography, was originally employed as a documentary adjunct to research work in the field and foley work for film. With the availability of high-quality portable recording equipment, it has subsequently become an evocative art in itself. Both processed and natural phonographic recordings are available. Field recordings can also refer to on-site recordings of musicians, such as those pioneered by John Lomax, Nonesuch Records and Vanguard Records, where the use of a recording studio for these recordings is impractical