Trevor Hogg chats with Will Cohen about making timeless visual effects for the Doctor Who franchise….
“The Milk team [as MILL TV] have been creating the VFX for Doctor Who since the series’ regeneration in 2005,” states Milk VFX CEO Will Cohen. “The team continued to work on Day of the Doctor as Milk when it launched in June 2013. Milk was recently commissioned by the BBC to create the VFX for the forthcoming 8th series of Doctor Who, starring new Doctor Peter Capaldi [In the Loop].” The iconic British TV series celebrated a 50th anniversary. “Television is a medium that often allows for true collaborative production partnership. The budgets and schedules create a situation where the VFX team is able to have a lot of creative ownership over what they are doing. As teams are smaller all the way up the chain, you get greater access to the client and so internal and external communication is a lot more streamlined. The Dalek Pods are a good example of being able to update and freshened the look of an asset; Milk created them for the Day of the Doctor. With an established franchise like Doctor Who, everybody always respects what has come before but they also have the desire to push things further with new ideas or embellishments.”
Unlike most current VFX projects photorealism was not the primary objective as the programme makes use of fantastical elements. “Few people know exactly what a spaceship re-entering the earth’s atmosphere actually looks like,” explains Will Cohen. “In science fiction the only things you can compare your work to, is things that have come before in film or TV.” Producing visual effects for the big and small screen is not the same thing. “Although TV and film have converged over recent years in terms of technical pipeline, shooting methodology and ambition, they are very different with different sets of disciplines. Time and budget constraints and also the greater level of detail and polish required for film to stand up to scrutiny on a 90 foot screen in the dark, mean that generally a movie’s trailer shots are the equivalent to the finished article on TV, creating a different set of rules.”
Day of the Doctor featured an updated spacecraft. “Milk had the chance in this Special to create a new form of Dalek fighter,” states Will Cohen. “This was designed for maximum speed and agility during the attack sequence and to create fast-paced, dynamic animations. We worked up the new design from the BBC’s Art Department concepts and developed it further to work for the style of animation we had planned. Modelled and textured in Maya, the new Dalek Fighter Pod maintained the classic elements of the Daleks with the added ability to release Daleks onto the ground after landing.” The Dalek Fighter Pods take part in the siege of Gallifrey. “For the dramatic sequences set in Arcadia, we created a large-scale 3D environment in Cinema 4D, of the city under siege. Milk designed huge fly-through shots to add a sense of drama and scale as the viewer plunges into the city alongside attacking Dalek Fighter Pods. Milk aimed to give the feel of a city that was near collapse, fighting for survival. The shots are frenetic with lots of explosions and laser fire. The buildings had to stand up to close up scrutiny because of the extreme camera moves. We ended up with around thirty wrecked ‘hero’ buildings that were then instanced [repeated] hundreds of times and the street filled with debris, explosions, fire, crashed saucers and tiny running figures. Working in stereoscopic 3D meant that often we were not able to ‘cheat’ effects and instead had to render smoke and fire in Houdini instead of using pre-filmed smoke and fire elements. As it was in Stereo, it was a great excuse to have lasers flying right past the camera!”
“The Time Lord paintings at the National Gallery were scripted as being ‘bigger on the inside’, as they are Time Lord art,” remarks Will Cohen. They also needed to look like traditional oil paintings. They are a pivotal point in the storyline as it is through the paintings that the Doctor and Clara witness the catastrophic battle and fall of Arcadia. They also form the entry point for the viewer to fly into the siege. One of the biggest challenges therefore was creating a framed painting that appears to be a two dimensional object but which, when the camera moves around it, is revealed to be a full 3D environment with depth, whilst still remaining within the picture frame. Working in Stereo meant that we had to cheat things to appear flat but still sit at the correct depth in the scene. We worked with Michael Pickwoad the BBC’s Art Director for Doctor Who on the look on the paintings. The reference we had from the BBC was a classic ‘old master’ oil painting, however, it looked quite dark. When we showed Nick Hurran, the Director, our shot of the Gallifrey Citadel he asked us to make the 3D painting look lighter and more like this.”
“There is always a lot of collaboration between us and the special effects team Real FX,” notes Will Cohen. “Particularly in the Fall of Gallifrey Sequence, where there were a lot of practical explosions, smoke and atmospherics. They used snow candles, which helped give the scenes depth and enhanced the stereo 3D.” Compositing, lighting, shader and rendering took longer because of show being in stereoscopic. The kind of shots we created were ambitious for TV, such as the fly-through shot into the siege of Arcadia thus there were many different lighting scenarios to bring together. Some of the older assets, such as the Dalek Saucer, needed to go through the look development process again so that they would work with our new renderer, Arnold. We took the opportunity to spruce up the textures and refine the shaders at that stage too. Regarding the lighting, the biggest challenge was lighting the Arcadia cityscape for the full CG shots. Fortunately we’d learned a lot from a night-time London flyover shot that we created for Channel 4’s Skins [more information on this can be found here: http://www.solidangle.com/news/skins-bright-lights-big-city/]. All of the geometry for each Arcadia shot was held in a single scene so that at render time all of the lighting, reflections and shadows interacted correctly to give the shot a sense of cohesion that is difficult to recreate using layered renders from separate scenes. The render time peaked at about 24 hours a frame [actually 48 hours because of the stereo] but Arnold was extremely reliable and the final renders did not require much additional compositing work.”
When questioned as to what was the biggest challenge for Day of the Doctor, Will Cohen replies, “The dramatic 3D Time Lord paintings at the National Gallery, through which the Doctor and Clara witness the catastrophic battle and fall of Arcadia, and which form the entry point for the viewer to fly into the city. One of the biggest challenges was creating a flat, framed painting that appears to be a two dimensional object but which, when the camera moves around it, is revealed to be a full 3D environment with depth, whilst still remaining within the picture frame. We also had to ensure that it worked well for 2D viewers as well as looking spectacular in 3D.” Cohen remarks, “Prior to the Doctor Who 50th Special, Milk already had substantial experience working in stereoscopic 3D on feature films Dredd, 47 Ronin , Narnia: Voyage of the Dawn Treader  and The Flying Machine . Generally speaking in 3D stereo, the planning process takes longer, and more time needs to be allocated to shots and renders. However, overall, this project was relatively straightforward with very few stereo fixes to do.”
“The shot featuring the exploding Dalek [within the siege of Arcadia] is a great example of all the departments involved [both at Milk and BBC Wales] coming together to create a sequence,” notes Will Cohen. “Technically this was one of the most demanding shots, as we were combining elements from the matte painting department and the 3D environment department, with a green screen shoot of the Doctors and a prop model of an exploding Dalek. This was bridged with three full CGI environments of battle-scarred Gallifrey, involving a complex, continuous camera move that stitched together all the separate elements. It was an epic shot for all departments. The shot combined matte paintings, 3D and FX from smoke plumes, flames and people running, to swarms of Dalek saucers and a frozen explosion on a practical Dalek; a complex composite to make one seamless shot. We also had to integrate smoke and flames, which were created in Houdini. The whole thing was rendered out in 3 separate parts in Arnold and composited together in Nuke. After we had assembled all the different elements the shot was re-sped to fit into the edit. The initial concept for this was to be three separate shots but we decided to make it more exciting and visceral by making this one long shot!”
“It was an honour and a privilege to be part of TV history!” reflects Will Cohen as to visual effects work contributed to Day of the Doctor. “We have a huge sense of pride at being part of such as massive and well-loved programme! We knew it would be big but didn’t expect it to be watched by 77 million people around the world.” Cohen notes, “The only assets that were new for Day of the Doctor and were reused for Time of the Doctor were the Dalek fighter pods [created for Day of the Doctor] and the Dalek saucers [having been upgraded for Day of the Doctor].
Planet Trenzalore and its surrounding asteroid belt needed to be created for The Time of the Doctor. “The asteroid field was brought in for visual interest,” reveals Will Cohen. “Made out of ice, it added to the feeling of bleakness and foreboding required to depict Trenzalore. We needed to ensure that the sizes and scales were correct, between the planet, the spaceships and asteroid field. The surface of the planet had been set up at the end of the previous episode, so there were visual clues from that. The challenge was to ensuring Trenzalore did not look like Earth [as viewed from space] so we had to make it more bleak and grey than Earth.” A dramatic pull back shot reveals the gathering of enemy spaceships. “In order to tell the story and set the scene at the beginning of the episode, it had to be a long shot and had to encompass numerous elements – to show the space environment and demonstrate the sheer number of the Doctor’s enemies’ spaceships from all over the universe surrounding Trenzalore. Given the number of elements and level of detail the shot was 20 seconds long, where usually a VFX shot would be between 6-8 seconds long.”
“We designed the Papal Mainframe from a concept by BBC Art Department,” explains Will Cohen. “We were given references such as a Blade Runner  feel, but above all the Mainframe had to be hugely majestic and impressive in size – a peacekeeping ship yet very powerful and an imposing, unstoppable force. We created this sense of scale by never allowing it to break frame we took the BBC’s design and developed it further. It was challenging to achieve the depth required, particularly in the shot where the TARDIS flies into it, where it had to feel vast so that the TARDIS would look tiny and much less significant. The concept for it was a huge illuminated city skyline at night-time, yet with a simple feel. Milk worked in conjunction with the BBC Art department who built the internal sets of the ship, which needed to mirror the external form of the ship.”
A signature Doctor Who moment involves the regeneration of a Matt Smith (Clone) into Peter Capaldi. “Milk created the effects depicting the Doctor’s twelfth and most powerful, violent regeneration ever – emanating immense power and energy – with plasma and fireballs flowing from him and culminating in a climactic explosion,” states Will Cohen. “Almost nuclear in its power, it causes a shockwave across the landscape in a shot that is viewed from a distance so that the viewers’ experiences the full power of the shockwave which comes right up to camera. Every time a doctor regenerates we try to push it further and make it stand out. This regeneration had to be more violent than ever before, thus we created a core of energy that provided enough power for a nuclear-like explosion – enough to explode Dalek saucers up in space. Adding another element to what we already had. We needed a core string of power that was bigger and impactful than previous regenerations.” A unique spin was sought out to make the event distinguishable from past occasions. “We always look for a new creative way to treat the Doctor’s regeneration, for example, we have focused on the eyes or a varying small section of face. This time the regeneration needed to be more dramatic than ever – and powerful enough for a nuclear-like explosion and of course no morphing effect was used. We used a ‘snap back’ so that the new Doctor just simply walked back into shot.”
“We had a very tight schedule and some long, effects heavy shots [particularly with the number of spaceships and particles required] but no particular issues!” reveals Will Cohen. “The opening shot was most challenging because we had to convey to the audience the sheer size and scale of it – with the number of spaceships – and have immediate impact. We had a lot of conversations with the producer about the composition of the shot, in order to make the most of the opening sequence. The regeneration was also challenging as there is so much expectation behind a Doctor’s regeneration especially following the success of Day of the Doctor. We needed to make sure that Matt Smith’s Doctor’s exit was as powerful and impressive as it could possibly be!”
“We were pleased with the way the shockwave worked, post-regeneration,” remarks Will Cohen. “It was an absolute pleasure to be working on our third major regeneration of a Doctor!” Milk will continue to work with the Time Lord. “We will yet again be endeavouring to push the boundaries of TV VFX. We are really excited indeed to be working on series 8; it’s a real privilege.” Cohen notes, “Many of us on the team have been privileged to enjoy a 10 year love affair with Doctor Who so to be able to carry on collaborating with the BBC Wales team on telling these incredible stories [for series 8 and beyond] fills us with joy and provides us with an opportunity as VFX artists to help push the boundaries of what can be done visually on television. A new series with a newly regenerated Doctor is in many ways like starting working on the show all over again. Doctor Who is a show that never, ever gets boring. It’s different every week. Peter Capaldi’s Doctor will be our 4th Doctor and we are very excited!”
VFX images and video courtesy of Milk VFX.
Many thanks to Will Cohen for taking the time for this interview.
Trevor Hogg is a freelance video editor and writer who currently resides in Canada.