Mobstar Media teamed up with Endemol UK and O2 to produce Cell, a hard-hitting series for mobile phone broadcast – without compromising on quality or plot.


O2 customers are currently enjoying a made-for-mobile action drama series that shares the production qualities of a TV show.

Filmed exclusively for mobile phone delivery, the 20-episode show, Cell, uses a stylized mix of live-action and CG to tell two parallel storylines for the same hero character in two-minute long episodes.

In the first strand, the man is locked in a lawless prison with no idea how he got there or why he’s there, and no hope of escape. All he has is a mobile phone and a mystery caller on the line.

In the parallel story, the same man is a wealthy Columbian, whose friend betrays him, leaving him with a life-changing choice.

Commissioned early in 2007 by O2, Endemol UK and its subsidiary Digital Studios worked in partnership with Brighton-based agency Mobstar Media to create the show.

“Our goal for the project was to blow people’s minds,” says Sean Coleman, executive producer of Endemol Digital Media Studios.

“We wanted to make a broadcast quality, sexy, stylish, beautiful-to-look-at piece of entertainment that would become a brand among its target audience. Basically, we wanted to make as much noise as 24 has, but in our own medium.”

Hired on the strength of its previous animated mobisode series Miami Vice Bust Ups, which accompanied the launch of Michael Mann’s film remake, Mobstar Media was given the task of pulling off a first for mobile entertainment – to create a series that mixed live-action with digital environments and VFX, at broadcast standards.


With a schedule of just three months to write, shoot and post the entire 40 minutes for the mini-series, a tight working relationship between Mobstar and Endemol was essential.

Throughout the production, Coleman was in daily contact with the producer, artistic director and senior editor at Mobstar. “It is the closeness of this working relationship that ensured that we all had the same end-point in mind, and that none of the precious little time we had to produce this piece was wasted,” says Coleman.

“It also meant that sign-off was the most painless process I have ever experienced.”

Nick Sneath, head of production at Mobstar Media, agrees: “We were extremely lucky with our partnership with Endemol, as I’ve never worked on a job where everything has run so smoothly with regards to client satisfaction.”

The first month of the production was spent script-writing, concept drawing, and rehearsing the actors. Mobstar Media’s art director Oliver Smyth created the concept art and storyboards with the assistance of Aaron Thai.

Smyth also supervized the 15-day greenscreen shoot to ensure the compositing process was as smooth as possible. The footage was shot on Digi-beta, then digitized and edited in Final Cut Pro by senior editor Dany Carlyle.

The post-production team, which consisted of three After Effects artists, a 3D artist, and a senior and junior editor, had just seven weeks to complete post.

In order to complete this work within the timeframe, the team had created many of the digital environments while waiting for the greenscreen edit.


The two storylines of the series – one set in a prison and the other in Colombia – required different treatments. For the latter, the Mobstar team had to plan out a variety of locations, taking into account the time of day, location and mood of the scene.

“Creatively, the biggest challenge of the project was compositing the actors into a digitally-created version of the Columbian capital, Bogotá,” says Sneath.

“It is always a challenge for any compositor to make something that has been shot inside with studio lighting look like it is, in fact, outside in the middle of the day. We decided early on that the end product would be stylized, giving us artistic licence to create a world more in keeping with a graphic novel.”

Working from Smyth’s sketches, Sneath and his team decided whether it was best to build each of the locations in After Effects in 2.5D or as a 3DS Max model, or to use a digital matte painting created in Photoshop.

“Budgetary and time constraints meant that exclusive use of traditional 3D packages would be too time-consuming,” explains Richard Frazer, an After Effects artist at Mobstar Media.

“So our 3D artist was given just a few very difficult environments to create, leaving the compositors to use a 2.5D solution for the majority of other shots.”

He outlines the process of creating a digital environment for an episode of Cell. “We started by creating surface textures in Photoshop from a huge bank of sourced photographs.

"We used the concept sketches to rough out 3D layouts using stand-in planes in After Effects, to make sure we covered all the final camera angles. When these were approved, we began applying textures to the surfaces and adding details,” he says.

The team took a slightly different approach for the prison storyline and built a physical set consisting of a wall, door and floor for the greenscreen shoot.

“All of the episodes of the Prison strand were still storyboarded and locations were sketched out, but the general mood and colour scheme was more consistent throughout, making the planning process much quicker,” Sneath explains.

“Having a physical wall made a big difference to the process as well, as we ended up using it in almost all of the different prison locations, dressing it differently, and adding different physical and digital set extensions to make it look like a different room/corridor each time.”

Advantages of using 3D software

The advantage of using true 3D instead of a 2.5D workspace in After Effects became apparent when creating the prison interior, says Sneath.

The space’s multitude of curved pipes and air vents proved too complex to build in After Effects. The downside to creating elements in 3D was the time required to render, as well as the integration of 3D elements into a pipeline where much of the work was in After Effects.

By rendering the 3D image sequences as RLA files, the After Effects artists were able to extract relevant information such as z depth. This meant they could add effects such as depth of field and colourization to the 3D objects and environments, explains Christian King, 3D artist on the project.

Despite a ten-machine renderfarm, the sheer number of layers required to create the final composite quickly became unmanageable, so pre-composing elements became vital.

“Environments such as the hotel lobby contained literally thousands of layers, which in terms of a traditional polygon-count may not be many, but when each one is shown on a timeline it can really slow down a workflow,” explains Frazer.

“So scenes would be broken down into elements such as walls, desks, chairs – each created as a separate pre-comp and then nested using the Collapse Transform feature. This also allowed each component to be quickly added or hidden, and for common elements to be shared between the artists.”

Virtual cameras were placed in the scene to match the shots from the offline edit, and lighting rigs were added to match the lighting of the actors and allow the scenes to be switched from day to night. Those shots without camera movement were rendered and used as matte plates, allowing further editing work to be done in Photoshop.

“Effects such as volumetric light could have been achieved in After Effects using third-party plug-ins, but it often proved easier to hand-paint these directly onto the Photoshop file,” said Richard Frazer.

Where shots required camera movement, the team pre-rendered stills of as much of the scene as possible, and used these renders as planes in front of the virtual cameras.

“For the most complex scenes, the camera moves were rendered with all of the thousands of construction layers in place, often requiring several days to render a few seconds of footage,” says Frazer.


With the backgrounds complete, the actors were keyed using the Keylight plug-in and rotoscoped into the shots. As it had been decided at the start of the project to give Cell a stylized, graphic-novel look, the scenes were heavily colour-corrected using adjustment layers.

“Some of the camera angles in the scenes became quite exaggerated and hyper-real, but we were constantly pushed by the artistic director to use a more ‘playful’ visual style that looked almost comic-book like,” says Frazer.

“It was fun not to get too bogged down in what looked technically correct, but instead concentrate on interesting compositions that still looked convincing,” he continues.

Sean Coleman says that the end product is very close to what he’d pictured: “At times it was as though the artistic director, Oliver Smyth had crawled into my head and sat there drawing my thoughts. On a ground level, it was a great collaboration, very artistic, creative and inspirational. And this is indicated in the amazing product that has resulted.”


Mobstar had to design two very different ‘looks’ for the main character



Before and after shots from a prison episode show the physical wall and floor.


Shots such as this one – set in the glare of Columbian midday sun, but actually filmed against greenscreen in a studio location – proved the biggest challenge for the Mobstar Media team. “We decided early on that the end product would be stylized, giving us artistic license to create a world more in keeping with a graphic novel,” says Nick Sneath, head of production at Mobstar Media.


Staying grounded

To achieve a credible blend of CG backgrounds and live action shooting, some set elements had to be real. “We had decided early on that all flooring should be real and filmed with the actors. During the shoot, photos were taken of the practical flooring so it could be used in the digital sets to extend the floors as seamlessly as possible.

“At times it was as though the artistic director, Oliver Smyth, had crawled into my head”



Episode 8: The penthouse location

This episode features a number of different locations, and the Mobstar Media team used a variety of techniques and elements to create these digitally.

While the final scene was always composited in After Effects, it would consist of 2.5D elements, in After Effects, enhanced with digital matte painting, 3D renders and the greenscreen footage plates.

The exterior of David’s penthouse apartment is the first location we encounter in Episode 8. Using the concept sketches as reference, the team modelled and lit the apartment in 3D Studio Max, then composited it in After Effects with a digital matte painting background that had been created in Photoshop.

Episode 8: The hotel location

To create the hotel hallway seen in Episode 8, several different hotel interiors were photographed and altered in Photoshop. “We had decided early on that all flooring should be real and filmed with the actors. During the shoot, photos were taken of the practical flooring so it could be used in the digital sets to extend the floors as seamlessly as possible,” explains Nick Sneath, Mobstar Media’s head of production.

The hotel lobby and street exterior were created in 2.5D in After Effects. “Both scenes had featured in previous episodes, but had been created for day-time shots, so not only did the camera need repositioning for each shot, the lighting set up and the colour scheme had to be completely changed from day to night,” recalls Sneath.

“As both scenes needed to be rendered from many different camera angles, including camera moves, both scenes had to be highly detailed and ended up containing thousands of layers.”



The background for this scene was created from photos from local hotels that were manipulated in Photoshop and reconstructed in After Effects in 2.5D.



This is a prime example of a typical floor extension, aided by photographs taken on set.

CREDITS

Project Cell: 20-episode drama for 02 network mobiles
Client 02, Endemol UK
Studio Mobstar Media, www.mobstarmedia.com
Software Adobe Photoshop, Adobe After Effects, Apple Final Cut Pro, Autodesk 3DS Max