Sony have been at the forefront of 4K acquisition with the release of their flagship digital cinema camera the F65 and their siblings – the PMW-F5 and the PMW-F55. The trio forms Sony’s high-end digital 4K/2K acquisition for cinema and high-end TV productions and commercials.
In addition, Sony has the ‘slow-motion’ beast – the FS-700 as a second tier 4K acquisition system, and the newly released PXW-Z100 towards the prosumer/consumer end. Hence, it makes sense for them to develop a common codec for 4K acquisition and workflow, which can work across their whole range in different flavours, depending on user requirements and deliverables. Sony refers to its 4K codec as XAVC. It is featured in more prosumer and consumer models as XAVC-S.
In the live session below, a panel consisting of Sony representatives and acclaimed cameraman and Sony Independent Certified Expert (who runs XDCAM-user.com – an excellent resource for Sony cameras), discuss the latest advancements in Sony’s 4K acquisition technologies and workflow.
Watch this video replay of the live session that took place at the Sony Booth during NAB 2014 in Las Vegas.
Video Source: Sony’s You Tube Channel
Sony is one of the manufacturers that have successfully implemented their 4K acquisition format in its current model line-up: PXW-Z100, FS700, PMW-F5, PMW-F55, F65 and in the latest addition to their DSLR (Digital Mirrorless Camera) the Alpha 7s full-frame camera.
In the presentation above Alister Chapman, a talented documentarian, who works on films and commercials all over the world, shares his experience with shooting on the Sony F5 and editing the raw material on his Macbook Pro. He was also impressed by the fact that in the future he will be able to upgrade his F5 with the better hardware capabilities of the current F55 model. The possibility to upgrade to a better new sensor with a global shutter, better colour gamut and the option to record 4K internally is really impressive, even though, the final price of this upgrade has not been confirmed. According to Peter Crithary, since 2005, Sony implemented more than 17,000 Sony 4K digital projectors in cinemas all over the world. In addition, he confirms that 4K is here to stay, and it will be part of Sony’s future development of new hardware.
The active pixel count of most 4K home displays is restricted to 3840 x 2160, a quadruple of 1920×1080 Full HD. It is sometimes referred to as Quad HD or Ultra HD, which is different from the Cinema presentation standard (DCI) which is a bit wider at 4096 x 2160 pixels across the image plane. The XAVC format covers both 4096 & 3840 horizontal sampling formats, allowing the XAVC production tools to be used in both cinema and television applications.
Sony’s F55 camera records 4K XAVC Intra frames at operating points between 240Mbps (@24P) to 600Mbps (@60P) within the camera. Theoretically, to suffice required bit rate for 4K 60p, four times in resolution and double the frame rate would require eight times of data. This sums up to 800Mbps, nevertheless, 25% of the data can be reduced based on encoding efficiency for progressive frame compared to interlace. The XAVC format covers both 4096 & 3840 horizontal sampling formats, allowing the XAVC production tools to be used in both cinema and television applications. 4K XAVC files can be considered a cost efficient alternative to camera RAW files.
In order to securely record such high data rate by a cost efficient yet compact media, Sony have developed the SxS Pro+ memory card family. The SxS Pro+ memory cards are compatible with all devices that have an SxS card slot, and achieve a sustained recording data rate up to 1.3Gbps. On a single SxS Pro+ 128GB memory card, the PMW-F55 records up to 50 minutes in 4K/24P or approx. 20 minutes in 4K/60P.
The 4K XAVC file size is similar to those of HD resolution files that are commonly used today. It is expected that 4K XAVC files will be one of the major driving force in expanding 4K production.