Component video in a 19mm digital cassette format which came out in 1987.
A format for digital video tape recording working to the CCIR 601, 4:2:2 standard using 19mm wide tape, allowing up to 94 minutes to be recorded on a cassette.
Being a component recording system it is ideal for studio or post production work with its high chrominance bandwidth allowing excellent chroma keying. At the same time multiple generations are possible with little degradation and D1 equipment can intergrate without transcoding to most digital effects systems, telecines etc. There are no colour framing requirements.
Despite the advantages, D1 equipment is not extensively used in general areas of TV production – not least due to its high cost.
Pank, B., Editor, 1994, The Digital Fact Book, 7th Ed, Quantel, Newbury, UK