Sky Italy prepares for the 4K era (part one)
It was early 2013 when Sky TV began to approach the technology of 4K or Ultra-HD, initially addressing the issue in coordination with other European broadcasters and, in particular, with BSkyB and Sky Deutschland – the aim being to examine the ins and outs of the technology in a consistent fashion.
The first complete 4K event shoot took place in March and centred upon the Ferrari Challenge in Monza, where Sky deployed Sony cameras. Shortly afterwards, around the end of April, Sky undertook a further round of 4K filming during a football match.
Of course, the story is a little more complicated than that timeline might suggest, with work beginning in January to analyse the technical specifications of the new format. Starting with the images and the collection of information through the shooting process, they set to analysing all the elements of the production chain. Along the way, they worked to identify the critical aspects and systems that would have to be updated in an existing TV profile, as well as considering which technologies were already available on the market to facilitate this trial.
“It is clear that 4K TV images require [much more] data than the present HD TV infrastructure is able to handle,” says Massimo Bertolotti, head of innovation and engineering, Sky Italy. “Therefore, any production and broadcast system has to be renewed from scratch in order to cope with the new [format].”
As the year progressed, the various elements involved in the 4K production fell into place – from the cameras derived and adapted from the film world, to the first 4K displays, and then, later in the year, mixers and contribution systems to manage end-to-end 4K content. In practice, this involved equipment capable of contributing 4K images shot in a location and transported to another location – for example, from a sports venue like a stadium to the TV production studio, and from there, eventually, to the viewer’s TV set.
“From these initial considerations, our laboratory has grown a lot and in the meantime we tried to compact and connect these available ‘single’ technologies to create an ‘ecosystem’, a chain of devices that could talk to each other and manage 4K live content,” says Bertolotti.
The next step was to coordinate a careful analysis of the shots taken to properly understand the results and interpret them accurately. The first response of the analysis was that the frame rate is definitely a key element 25 frames per second – which were more simply and easily supported by the existing chain in HD and many present systems – were not sufficient to achieve the desired quality of sports images.
“So on the one hand, [whilst] the very high resolution surely brings an advantage, it is equally important to consider the frame-rate to ensure that the Ultra-HD may represent a justifiable qualitative leap forwards,” says Bertolotti.
This progression is particularly clear in the filming of spectacular live events like sports where several significant factors are combined: the abundance of movement, the inability to undertake post-production process, and the fact the sheer speed of events sometimes makes it difficult to select the best camera angles.