35 – Videotape recording
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Publisher Summary
This chapter focuses on videotape tape recording. Videotape track angles depend upon whether the tape is moving or stationary. Magnetic tape cannot transport recording or playback head fast enough to accommodate the high bit rate of digital video recording (or the high frequencies of analog video recording). Videotape tape recorders (VTRs) move the head rapidly, across slow-moving tape. In a typical digital VTR, the head is tilted at a steeper angle from the vertical, the wrap angle is reduced, and several passes and several heads are used to record each field. Videotape track angles depend upon whether the tape is moving or stationary. Three analog video recording methods are dominant: component, direct color, and color-under (or heterodyne). For studio recording, analog VTRs are obsolete (though many Betacam VTRs remain in service). The chapter also explains that in a digital VTR, data is arranged in small packets called sync blocks, each short enough to be recoverable in its entirety even at fast forward or rewind speed.