The new Channel 4 HD is available on Sky channel 140, and kicks off with high definition versions of shows like Ugly Betty and music events including The Scissor Sisters and Keane live in concert.
Further content will be added in the coming months, including classic and contemporary movies and shows like HollyOaks, which is expected to be broadcast in HD from next spring.
The launch Channel 4 HD represents "an early, cost efficient entry" into a valuable, emerging market, said Rod Henwood, director of new business at Channel 4.
The new channel is available immediately to all Sky HD subscribers without an additional subscription.
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