Introduced in 1997, the HDCAM is a high definition version of Digital Betacam. This equipment features 8-bit DCT compressed 3:1:1 recording in 1080i-compatible (1920x1080) resolution, as well as adding 24p and 23.976 PsF modes. The recorded video bitrate is 144 Mbit/s. The audio is similar, with four channels of AES/EBU 20-bit/48 kHz digital audio. This system is used in Sony's range of cinematic CineAlta products.
Sony HD Camcorders
Making it debut in 2003, the HDCAM SR packs an awesome punch of recording to a bitrate of 440 Mbit/s and at 4:4:4 format to 10 bits. The increase in particle density over its sister HC CAM allows for improved HDSI signal capture in a higher bandwidth, and allows for a doubling of the bitrate. This means a reduced compression for the single 4:4:4 stream, or alternatively to run two lots of 4:2:2 at the same time. Using the improved MPEG-4 Studio Profile, the compression allows for twelve audio channels.
Playback of Betacam Variants
One of the classic benefits of some HDCAM VTRs, the SonySRW-5500 for example, is the ability to play the old Betacam varieties of tape as well as the modern formats. In fact, the contemporary tape lengths are modelled on the Betamax models - S tapes record 40 minutes, and L tapes carry over two hours. In the new 24p mode, however, this storage capacity can be increased to run 50 and 155 minutes respectively.
HDCAM tapes are black with an orange lid, whilst an HDCAM SR tape is black with a cyan lid. The 440 Mbit/s mode is known as SQ, and the 880 Mbit/s mode is known as HQ. This mode is currently (2005) available in portable models only.