New systems include additional Sony HDCam-SR multi-format recording and playback facilities, and enhancements to an existing Avid Adrenalin system - including Dolby audio tools and Avid ProTools LE audio editing software. It was installed by international systems integrator ATG Broadcast, which also handled Phase 1.
The National Geographic HD channel began broadcasting last summer, becoming the first channel from a third-party broadcaster to join Sky's burgeoning HD line-up.
Nat Geo facilities manager Simon Brett said: 'The transition from SD to HD broadcasting has proceeded very smoothly, and audience reaction to what is now practically a home-cinema experience has been extremely positive.'
ATG Broadcast sales director Alan Pimm said: 'Nat Geo's excellent ratings confirm the value of combining high-quality factual content with high definition delivery. 1080i [HD] broadcasting has taken off faster than anyone in broadcasting could have predicted. It is likely to become even more appealing as 1080-native screens replace 720-line displays in the consumer market.'
Nat Geo has made content available on VoD platforms including iTunes, BT Vision and Orange. On 1 March it launches Nat Geo Wild, a new 18-hour channel on Sky and NTL/Telewest.