Chris Evans, broadcast expert at research and consulting specialist Futuresource argues the case for 8K
The ongoing drive for ever-higher resolutions has been a familiar story in the world of video acquisition for many years. But, after IBC 2018, talking about the practical application of 8K is no longer taboo.
Japan’s state broadcaster, NHK, has long been the driving force behind 8K. Manufacturers have been committed to developing an ecosystem of products that can support the 8K broadcast standard, ‘Super Hi-Vision’, in time for the Tokyo 2020 Olympics. However, with many other broadcasters still occupied with upgrading their portfolio of HD channels and the limited availability of 4K content, meaningful use of 8K technology in the wider industry can seem distant.
Shortly before IBC, 8K held a notable presence at IFA 2018 in Berlin, as Samsung, Sharp, LG, TCL and Toshiba all dedicated space at the convention to showcase 8K consumer displays. Samsung and LG incorporated spectacular reveals of their 8K TV sets into their press conferences, whilst Sharp (Sharp 8K TV pictured above) emphasised their development of an 8K ecosystem, which includes both their display and the 8C-B60A camcorder, which has already begun shipping in Japan and China. The continued focus on higher-resolutions by TV manufacturers at the show indicates that it won’t be long until they begin their attempts to drive 8K into the home, as they did with 4K.
Though adoption of 4K in broadcasting has been slower than was first anticipated, 4K acquisition has been accessible for several years. 2017 was a particularly significant year for 4K adoption in the camcorder market, as it truly became mainstream. Cost effective 1” sensor camcorders brought 4K to the lower-end of the market, as sub $5,000 fixed lens camcorders have fuelled a 9% point annual increase in the worldwide market share of 4K capable camcorders sold by Sony, Panasonic, Canon and JVC, to account for a total of 32% of worldwide camcorder volumes.
The accessibility of 4K acquisition has allowed workflows to mature and, with this, has come a greater awareness of the benefits of over sampling (acquiring video footage at a higher resolution than is necessary for the final output). It has been proven and accepted that recording video at a higher resolution and down-sampling the footage for final delivery will result in an improvement in video quality. The flexibility of having a larger canvas of pixels to work with also enables more creative options in post-production, from digital zooms and cropping in and recomposing shots to improving the accuracy of digital stabilisation and VFX tasks.
The use of 8K in live broadcasting may be very limited for the foreseeable future on a global basis, but the benefits of 8K acquisition are already apparent due to the proven use-cases of oversampling. There is an obvious use for 8K acquisition at prestige events and in select cinematic instances to begin preparing a library of 8K content, but 8K is not just about futureproofing. The same learnings made from using 4K acquisition to create HD content can be applied with 8K, but to an even greater degree - especially in the case of using 8K for HD formats. Capturing 7680 x 4320 pixels to create a 1920 x 1080 image may sound like complete overkill, but it’s precisely that factor of 8K being 16 times bigger than HD that makes oversampling 8K footage a more perceptible step-up than 4K. 8K cameras will not immediately replace 4K or even HD cameras, but their enhanced capabilities for oversampling allow them to be used in a completely new way.
At IBC 2018, Panasonic demonstrated a new camera that will be available next year that uses 8K acquisition as a tool to facilitate more efficient HD capture. Panasonic are calling this technique in use, “region of interest” or ROI. ROI allows up to four independent HD crops to be taken from a single 8K source camera (for instance, creating wide, mid and close shots simultaneously of a scene). In a practical application, this can reduce the number of cameras needed on a production, as multiple shots can be captured by a single camera operator. Sony’s UHC-8300 8K studio camera also enables a similar kind of flexibility, as it can simultaneously output 8K, 4K and HD signals. This facilitates more flexible workflows - for example, live feeds in 4K and HD could be sent to a video switcher for use in live coverage, whilst the 8K signal is taken directly to a recorder for archival purposes.
As the adoption of the 4K UHD formats grows, there will be a greater need for 8K where instances of oversampling for 4K content is necessary. The reason that 8K will gain ground in acquisition in the immediate future is due to the new possibilities that it creates in production. 8K cameras will begin to see growth primarily through their use in mixed resolution production environments, deployed among an array of HD and/or 4K cameras.
IBC marked a significant step forward in the eventual adoption of 8K. Though its use as a broadcast format will remain niche, the potential it has to enable new techniques in acquisition are abundant. With NHK set to start broadcasting their 8K content in December this year, the acceptance of 8K is already well under way.
Chris Evans is Broadcast & Professional Video Equipment expert at Futuresource