NAB 2017 Submission by Nic Dugger
For millions of Americans, the National Christmas Tree Lighting at President’s Park (White House) in Washington, D.C. is a tradition that they look forward to every year, kicking off the holiday season in the nation’s capital through a fun event with rich historical roots. Held on December 1, 2016, the 94th edition of the ceremony featured musical performances from James Taylor, Chance the Rapper, Kelly Clarkson, Garth Brooks, Trisha Yearwood, Marc Anthony and many more artists, with President Barack Obama throwing the switch to light the tree for the last time in his term.
Broadcast annually, the most recent ceremony marked the first time that the National Christmas Tree Lighting was made available to television audiences in 4K Ultra HD. Presented by the National Park Foundation and the National Park Service, and produced by Bounce AEG, the event was televised December 5, 2016 on DIRECTV’s live 4K channel, and simulcast in high definition on the Hallmark Channel. This was made possible through a partnership between the National Park Foundation and the Hallmark Channel.
The addition of a 4K television partner to the event had a significant impact on the production and post-production technology workflows involved, and it took close collaboration between the various teams to meet all of the project’s objectives and tight deadlines.
“We needed to deliver two shows in a very short turnaround time, with different network specifications that required us to record both 4K and HD 1080 masters,” said Sean Kelley, on-site Technical Manager for the production. “Even after considerable advance planning, we spent further time together in the truck to make sure we were fully aligned on deliverables. Understanding your deliverables list is probably the most important aspect of working in 4K.”
Steve Meyer, who served as Technical Director for the project and shared pre-show Technical Manager duties with Kelley, concurred. “All of the departments – from mobile production truck provider TNDV to the production and post-production teams – really came together to make everything work and get everything to spec, so we could turn the media over to post production immediately after the event with no roadblocks in their way.”
By all accounts, those efforts were successful, resulting in shows that lived up to the stature and expectations of the event. “Thanks to our partnership with Hallmark, we were able to share this time-honored national park tradition with more people and in new and different ways using 4K and high definition,” said Angela Hearn, senior vice president of marketing and communications at the National Park Foundation and executive producer of the National Christmas Tree Lighting. You can watch the 2016 National Christmas Tree Lighting on demand and learn more about the event’s history at www.thenationaltree.org.
Powering Live Production
The DIRECTV and Hallmark Channel television specials were far from the only significant video destinations that the on-site production supported. Pre-created content and live feeds were shown in HD on large LED screens for image magnification (IMAG), enhancing the live experience for on-site crowds, while production feeds were also provided to the more than 50 media outlets covering the event.
In addition to supplying the mobile production truck, production equipment, and key engineering personnel for the project, Nashville-based TNDV also provided the cabling infrastructure that brought live video to the press corps, IMAG screens, back-stage monitors, and on-site staff ranging from electricians to show management. Single-mode fiber connectivity was used to run feeds over long distances throughout the compound, with AJA FiDO bricks used to convert the fiber signals to HD-SDI for monitor connections.
For TNDV owner Nic Dugger, this year’s tree lighting ceremony held particular sentimental significance. “While this was our first time supporting the National Christmas Tree Lighting, we worked on a country music special with President Obama in his first year in office, back when TNDV only had one truck. To be there with our eighth truck as he wraps up his eighth year as President was a huge honor.”
That truck was Exclamation, TNDV’s 53-foot, double-expando Class A mobile production center, which first hit the road earlier in 2016. “Exclamation was our optimal truck for this event, not only because of its 4K, quad-link architecture, but also because it has space to accommodate a large crew,” Dugger said. Serving as the on-site broadcast facility, 25 of the truck’s 30 seats were filled by four full-time TNDV personnel and the project’s many freelance professionals.
Exclamation’s Imagine Communications Platinum routing switcher formed the nerve center of the production’s video and audio infrastructure, with 24 integrated HView multiviewer outputs enabling customizable displays tailored to each user’s needs both within the truck; and at other on-site locations including production offices.
TNDV supplied nine cameras to cover the event, including eight Sony HDC-4300 camera systems that delivered both 4K and HD signals to the truck over SMPTE hybrid fiber connectivity. Four of the Sony cameras were deployed in hard camera configurations with box lenses – three at front of house and one a house left slash – with another Sony unit on a large jib and three more used in hand-held operation. The ninth camera, a HITACHI SK-UHD4000, followed the event’s hosts during pre-show activities and captured Hallmark-exclusive host bumps to commercials.
The quad-linked 4K and HD signals were switched in the truck using Exclamation’s Grass Valley Kayenne switcher and K-Frame. A combination of mix effects (ME) transitional linking and source table substitution enabled seamless switching of not only all four quadrants of the 4K picture, but also the HD inputs and output.
“With quad-link, you’re effectively switching four signals instead of one, each of which forms as section of the 4K image,” explained Meyer. “We had both the quad-link 4K and 1080 HD signals from the cameras coming into the K-Frame, and by linking the ME busses, I was able to switch the 4K show and the HD show simultaneously, including transitions such as the pull of the fader bar. That made my job easier during the show, allowing me to cut as normal and get both outputs.”
Exclamation’s on-board Abekas Mira server provided pre-show clip playback for the large on-site LED screens, while a custom-configured Ross Xpression Quad 4K character generator with an AJA Corvid 88 I/O card, supplied by Chris Marsall of CGLA Studios, served as the primary graphics platform. 4K, quad-link output of the key and fill signals from the Ross Xpression was routed to both the Kayenne switcher and to Cobalt Digital processing equipment, the latter of which down-converted the 4K outputs to HD. The resulting HD key and fill were then also routed to the switcher as inputs, enabling the 4K graphics to efficiently serve both the 4K and HD productions.
Camera ISO feeds and the broadcast line cut were recorded separately in both 4K and HD. A total of 12 AJA Ki Pro Ultra units recorded the 4K signals, while 12 Ki Pro Rack units recorded HD. In addition to the clean line cut, a ‘dirty’ line cut with keyed graphics was also recorded in both HD and 4K, saving subsequent post production time by avoiding the need to redo most of the graphics.
On the audio front, Studer Stageboxes from HARMAN Professional Solutions delivered every audio feed from the stage to the truck, where a broadcast audio mix was created with Exclamation’s Studer Vista X large-scale console. Multi-track audio was recorded on an Avid Pro Tools system for subsequent post production remixing, with Sound Devices PIX 270i recorders also capturing the MADI streams as backups. An RTS matrix intercom system rounded out the audio infrastructure, with more than 100 ports used for communication.
“The audio element is always of critical importance when producing a show this immense,” said Dugger. “We always play especially close attention to the positioning of our crowd microphones to ensure that viewers have that feeling of being right there in the crowd along with everyone else. It’s a significant part of the overall experience that is too often overlooked in mobile production.”
Once the event ended, TNDV’s recorded 4K and HD media files were immediately turned over to the post production team for editing. The quick turnaround time precluded editing natively in 4K, so the show was edited in 1080/23.98PsF, then matched and conformed to create the 4K version for DIRECTV. The 23.98fps HD result was then converted to 29.97fps interlaced HD to meet the Hallmark Channel’s delivery requirement.
“It would have been great to edit directly in 4K, but there just wasn’t enough time to do so,” said Uppercut Media’s Mark Stepp, who served as editor on the television specials. “Because we were matching the 4K version to the HD, it was crucial that time code was handled perfectly between the HD and 4K recorders so everything lined up in post. The technical teams did a great job of that.”
The 4K and HD files from the AJA recorders were copied onto an Avid ISIS platform for editing with Avid Media Composer in the clips’ native ProRes format. Two Media Composer bays worked on the project simultaneously, one editing the musical performances while the other formatted the show, got it to time and added further graphics. The sequences were then merged and refined to create the final deliverables. Audio mixing was performed at concurrently, and with editing completed ahead of schedule, the audio team had time to sweeten the audio. The finished, file-based outputs were delivered to the networks using Aspera transfer acceleration technology.
“Because we were able to get a dirty line cut in 4K and HD, we were able to use roughly 80% of the graphics directly from the live production, which saved us a tremendous amount of time,” said Stepp. “For those graphics that we changed in the HD edit, we did need to re-do them when we created the 4K version, but that’s a lot less work than if we’d needed to do all of the graphics in post.”
Up to the Challenge
Very few live productions are executed without facing any challenges, and the emerging nature of 4K technology all but ensures that Ultra HD projects will have some obstacles to overcome. “Everyone coming into the project knew it would have challenges but were very positive and optimistic, going into it with open eyes and open minds to make it work,” noted Stepp.
While many of the challenges the teams faced had nothing to do with technology – for example, rain significantly altered the setup and rehearsal schedule – others reflected the evolving 4K support in the equipment. The switcher required progressive segmented frame (PsF) signals to support the 23.98 time base in 4K, while the post production team had been expecting progressive (P). Initially uncertain of what the ultimate interlaced conversion would look like from PsF sources, on-site tests prior to the show confirmed that the PsF media would be just fine.
Such nuances highlight the need to be particularly specific in communications about deliverables in the 4K realm. “The terms P and PsF are sometimes used almost interchangeably, and while you can sometimes take that for granted when working in HD, you can’t make any such assumptions in 4K,” explained Stepp.
The Ross Xpression system also needed an upgrade to support PsF at 23.98 frames per second. “Ross worked very closely with us to deliver a new build of the software that met our requirements,” said Marsall.
During initial testing, the team also had difficulty getting their full-raster 4K graphic elements to play reliably, as they were exceeding the throughput of the system hosting Xpression. After some experimentation, Meyer broke the 4K motion graphics into four quadrants in Adobe After Effects, and reassembled them numerically on the Xpression canvas to form the complete Ultra HD image. The quadrants played in sync seamlessly, solving the issue.
Words of Wisdom
“It’s important to realize that there’s a learning curve, just as there was from SD to HD,” said Meyer. “For example,
while quad-link allows 4K to be done on well-established broadcast equipment, which is great for operational familiarity, it takes four times as many processing resources, so you won’t be able to do as much as you could on the same gear in HD. And you’re often working with the equipment in 4K for the first time on-location, so be prepared to deal with the unexpected.”
“To my technical director counterparts, allow lots of time for advanced programming and testing of the switcher to ensure proper linking of the quad-split 4K,” he continued. “Manage your resources carefully, and know that you won’t always be able to accommodate last-minute requests as easily as you’re used to in HD.”
“Especially when you’re working in both 4K and HD in parallel, the workflow considerations can grow exponentially,” said Stepp. “Not only are you dealing with two separate targets, but one of them is still an emerging technology. I’ve worked on ten 4K projects now, and almost every one of them had a different combination of cameras, recording formats and deliverable specifications.”
“Working in 4K reinforces how important it is for the post team to be involved in the planning of the production side right up front, to make sure everyone’s aligned on formats, frame rates, and so forth,” he advised. “Production and post must work closely together to make sure you don’t end up in a corner. 4K trouble is four times bigger than HD trouble. Good communication – and early communication – helps avoid that.”
Ultimately, like any discipline, success in 4K starts with having the right attitude. “It’s important to keep an even keel on location when you’re breaking new ground,” concluded Dugger. “Of course, test everything beforehand to the extent that you can, but you know you’re doing things that haven’t been done before, so expect the unexpected and embrace the challenges. That’s what helps move our industry forward.”
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