Adrian Pennington weighs up the options, from high-end media like SR and Redmag, to robust memory cards such as SxS and P2, and the latest prosumer options including XQD.
As tapeless production becomes the norm, costly errors in hand ling the media are a concern. While security measures like backing up the day’s files are widely acknowledged, the introduction of new recording media into the market can confuse matters.
There is high-end media like Sony’s SR Memory Card and Red’s Redmag, both solid-state drives built into a cartridge form and capable of recording hi-res uncompressed footage at high frame rates.
Next come robust memory cards like SxS (Sony and SanDisk) and P2 (Panasonic), and then prosumer media like CF (Compact Flash), SD (Secure Digital), SDHC (Secure Digital High Capacity) or the new XQD cards, seen as a successor to CF.
“Despite being cheaper, XQD cards are still capable of capturing low-compression HD footage from a wide variety of recording devices,” says Simon Gannon, head of marketing at cloud video production platform Aframe.
As most solid-state media is fairly similar in terms of physical robustness, the main difference is in the read/write speeds. Because the speed at which a card can read or write determines the quality of the recording format that can be captured to it, producers are left with the standard production equation of quality versus cost.
“Cheaper cards bring higher risk of lost footage,” warns Don Grant, systems manager at broadcast hire firm Procam Tele vision. “Compact Flash, for example, is nowhere near as reliable as, say, SxS or P2. The latter is made by the same manufacturer as the camera it will be used in, so if you do have an issue, you can pretty much guarantee their support.”
Then there are portable file-based recorders that take the HD-SDI output of a camera to obtain a higher-quality signal. These are made by the likes of AJA, Atomos, Blackmagic, Codex, Cinedec and Convergent Design.
“By some distance, the most important step in deciding which recording device to use is to ask your post house,” says HotCam technical supervisor Daniel Farmer. “They will tell you whether the recording format and signal input is compatible and of high enough quality to make it smoothly through post without inadvertently costing you more time and money. It’s all well and good being able to take an HDMI signal and record it to a low-cost SD card, but there’s always a compromise when using consumer products.”
Perhaps the main advantage of using a recorder is to gain access to a higher-data-rate codec that enables the material to satisfy the broadcaster’s requirements, such as the 50Mbps rule that most UK broadcasters, including Sky and the BBC, use for HD acquisition.
Another advantage is the ability to gather the material in a codec that is directly usable in the edit system. “An Avid system would prefer a DNxHD codec, while an Apple FCP system would prefer the Pro Res HD codec,” says Procam head engineer Perry Mitchell. “Even then, there are often several versions of these, so it’s important to check that the version required, perhaps due to data size restraints, is available on a particular recorder model.”
The latest memory recorders are designed to create native Apple Pro Res, Avid DNxHD, RAW and HDCam SR files, which are much greater in size than the files many in the industry have been used to.
“It is a very competitive area and none of them tick all the boxes,” says Alain Lolliot, technical operations manager at Pro Motion Hire. “Some recorders offer very low compression, around 145Mbps, but do not offer 50Mbps, which is all producers need for HD broadcast [Convergent Design’s nanoFlash does offer 50Mbps but has no in-built confidence monitoring]. The knock-on cost in having to manage larger file sizes needs weighing up.”
Fortunately, facilities and hire houses can play a guiding role for the production manager, who usually takes ultimate responsibility for workflow and the assets produced.
“They need an understanding of the processes involved – what can go wrong and what to do if something does,” says Lolliot.
High on the PM’s list should be assigning the vital role of safeguarding the show’s rushes. Drama productions would probably use a higher-spec camera and have a staffed camera crew including a digital imaging technician (DIT) on set to deal with look management and data.
Ob docs with higher shooting ratios, smaller cameras, smaller crews and smaller budgets might only back up material to a cheap RAID array at the end of the day’s shoot, and the team typically view material on a laptop or portable device.
There may be enough in the budget to assign a data wrangler to supervise the data but, as Lolliot observes, “often the task of back-up and transfer falls to junior producers, runners or camera assistants”.
Problems are exacerbated as these tasks often need to be done at the end of a long day, so time in the schedule is as much of a prerequisite as training.
“I’ve seen people scrabbling around looking for footage due to a misplaced file or broken folder structure on too many occasions,” observes Farmer. “It can seem quite easy just to sit and transfer files, and the cost of a dedicated media manager is something a lot of producers want to avoid. That is a mistake. Without footage, the entire shoot is a write-off.”
While there are some real cost savings to be had in shooting on card instead of tape, production companies have had to come up with their own solutions to clear the cards so they can be reused. This means somebody copying the data onto hard drives, via a laptop.
“This is not always practical in the field, and hard drives are much more susceptible to failure or damage,” says Grant. “There has been little choice, other than to adapt. No new tape-based HD cameras are coming onto the market, and already technology is developing further still.”
With the recent arrival of the QXD format, a new wave of cameras and recording units can’t be far behind.
Ironically, it is tape system LTO that is considered a more attractive option for archive than alternatives such as optical disc.
“Each £50 optical disc holds 50Gb of data and takes up to an hour to write 90 minutes of rushes,” explains Lolliot. “So if you have 1.5Tb of data to back up, that would require 30 50Gb discs, and take 30 hours to write, at a cost of £1,500 for the media alone. A 1.5Tb LTO-5 tape would take about three hours to copy, at a cost of around £45 in total for the media, saving you 27 hours and £1,455 in media, let alone man hours and sanity.”
Preserving these much-cherished luxuries out in the field could be where tapeless truly comes into its own.
GOING TAPELESS
24 HOURS IN A&E
The second series of Channel 4 ob doc 24 Hours in A&E is being filmed in HD using more than 90 cameras and with an innovative workflow.
The Garden Productions will produce 14 hour-long episodes from its six-week round-the-clock shoot on location at London’s King’s College Hospital. “The first series was shot SD to SX tape, so going HD and tapeless for this series made a massive difference to our approach,” explains Garden managing director Scarlett Ewens, who devised the workflow with The Farm.
“The sheer volume of data – 160Tb – and the way the media is being put together is different to a conventional ob doc so it made more sense to manage the media at the front end of production. The Farm is responsible for storing and QCing media on location and transferring all the data to the edit so that the grey area between location and facility house, which can lead to problems, is bridged.”
The 91 fixed-camera feeds are cut by directors in two custom-built galleries, with the feeds recorded to Avid Airspeed. Media is immediately captured to Isis via Interplay’s transfer management at 50Mbps 4:2:2 and copied to LTO-5 tape with associated metadata written in Linear Tape File System (LTFS), and is then couriered to The Farm’s central London data-handling facility.
Once there, the tapes are ingested into Unity for editing on Avid. “The adoption of this procedure means we don’t have to archive once on site and again at the end of production,” says Ewens.
One alternative would be to record directly to XDCam HD disc and keep the discs as a more traditional archive, but this would have meant buying approximately 8,000 discs.
David Klafkowski, technical director at The Farm Group, concludes: “This represents a sea change in the way in which we can run a post operation on location.”
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