January 12, 2011


Baseblack contributes its own magic to the latest Harry Potter film
For the seventh time, visual effects studios are dazzling audiences, providing digital magic to create the on-screen magic required in the latest Harry Potter story line. And yet again, the film’s effects are being applauded by moviegoers. So far, they are also still in the running for an Academy Award, as the list of potential candidates continues to grow shorter.

A number of studios have worked on the Harry Potter series since its initial run in the theater, and for this latest installment, most of those facilities are located in the UK—Cinesite, Double Negative, Framestore, and The Moving Picture Company, to name a few. Indeed, most of their work was exceedingly complex and provided very exciting moments in the film: for example, the shape-shifting that resulted in the seven Harry Potters (MPC), the great escape scene involving Harry and his friends at the beginning of the movie (MPC), the intrusion of the Death Eaters at the wedding (DNeg), destruction of the Lovegood house (DNeg), the unforgettable scenes with Dobby and Kreacher (Framestore), the appearances of the beautiful Patronous in the shape of a deer (Cinesite). (For an in-depth look at this complicated work, see the January/February 2011 issue of CGW.)

Another UK-based facility, Baseblack, also contributed greatly on the film. Despite being the smallest UK VFX facility to work on the project, the team has created the largest number of visual effects shots for Harry Potter & the Deathly Hallows Part 1. In all, Baseblack’s work encompassed 45 sequences and more than 300 shots. The boutique studio’s work included every appearance of the famous golden snitch and the chilling final sequence at Dumbledore’s tomb involving a huge lightening storm. In addition, the Baseblack team worked on:

  • Spells, including Obliviate, the Deluminator, and the classic Lumos
  • Hermione’s magic handbag
  • The horcrux locket’s underwater attack on Harry
  • A wand shoot-out in a cafe
  • Turning a summer river scene into a frosty mid-winter landscape
  • Major background replacement throughout the film
  • The moving photographs in newspapers

Here, various people on the Baseblack team talk about the studio’s work on Deathly Hallows with CGW chief editor Karen Moltenbrey.

Did you work on any of the other Harry Potter films?
Executive producer Stephen Elson: Baseblack worked on two previous Potter films. In fact, Azkaban was pretty much Baseblack’s first big job, and we did around 30 shots: CG crows that flew above or hopped and landed around the executioner, plus a bunch of miscellaneous comps—basically anything that happened in and around the two sequences set at Hagrid’s hut. In The Order of the Phoenix, for the Weasleys' family Christmas scene, we built a CG flying Father Christmas toy that buzzed around the table as everyone sat down to tuck into their turkey. We also added CG snow over the Christmas tree and bruises to Mr. Weasley’s face. On both films, though, we were brought on at a late stage to help out. Deathly Hallows marked the first time that we’d been a contracted major vendor from the show's outset.

Can you elaborate more on the sequences for Deathly Hallows?
VFX Producer Kate Phillips: We created various spells and objects that recur throughout the film. These included the Obliviate charm, which had never been seen before, and which Hermione uses to wipe her parents' memories of her at the film's opening. Director David Yates was keen that the process should not seem painful, and that it should be a subtle effect that wouldn't distract from the performances, so we ultimately went with a small-scale fractal displacement effect, which, along with a gentle regrade, sold the physical manifestation of the effect in a suitably low-key series of shots. More obvious was the Deluminator device that Ron receives from Dumbledore's will, and which can be used to turn off and restore lighting in any environment. Baseblack was given a largely free hand to design the look for how the object, which looked like a large cigarette lighter, worked; we came up with a look in which, whenever Ron activates the device, all the lights in the area peel off like comets and fly across the room to be physically sucked into the Deluminator. Our most prominently featured CG object was the golden snitch, which had been fleetingly seen in previous Potters, but here took on a slightly different character, hanging around Harry like a faithful dog. Its recurrence required us to animate it into several different sequences, as well as come up with a number of solutions for the look of its wings as they fold, unfold, and hover.

We also took on a number of specific action sequences. In the first one, a pair of disguised Death Eaters track down Harry, Ron, and Hermione to a cafe in the West End, where they've sought refuge. The fast, brutal wand battle that ensues was designed to seem like a magically enhanced take on a classic gunfight, and was a great opportunity to feature magic in the real world. We used the same look for a twilight chase scene as the Snatchers pursue the trio through the woods. Another scene sees Harry diving into a frozen lake to retrieve The Sword of Gryffindor, at which point the horcrux locket comes to life and tries to strangle him. We animated the locket, which dragged Harry around and bit into his neck, and created a vortex of bubbles streaming off him, thus increasing the violence of the scene. We also contributed to a sequence where Bellatrix turns on the Snatchers involving a CG snake wrapping around Greyback's neck and a black leather whip rope that shoots from her wand and yanks Scabior off his feet.

We were also responsible for a large amount of miscellaneous work throughout the film, ranging from snowing up landscapes and adding frozen breath, to winter scenes that had been shot in summer, to the trademark Potter effects, like disapparition and moving newspaper photographs.

Finally, we delivered every shot in the film's dramatic closing scene as Voldemort smashes open Dumbledore's tomb and steals the Elder Wand from his corpse. This was a sequence that was almost entirely created by visual effects, combining a small section of the set with motion-control passes of Ralph Fiennes and Michael Gambon—who were never on set together—into a virtual Scottish loch environment, complete with CG trees, water, and mountains. Wider shots comprised a matte painting of the island, combined with a CG cloudscape into which Voldemort fires a lightning storm.

Would you please give us details about the content creation process for the sequences?
VFX supervisor Matt Twyford: Our work on the film was heavily weighted toward 2D since, as a small facility, we don't have the heavyweight 3D pipeline of some of the film’s larger vendors. As such, we were keen to find compositing solutions wherever possible. We worked with a combination of (Apple’s) Shake and (The Foundry’s) Nuke, augmented by (Imagineer Systems’) Mocha and (The Foundry’s) Furnace (the latter was invaluable for addressing some particularly challenging neg scratch clean-ups). Our small team meant that most artists were responsible for their own prep, although we had one team member dedicated to rotoscope who lent a hand where necessary on heavy shots. Sequences that might have called on 3D were often completed using fairly old-school techniques—for example, the majority of the wand blasts were hand-painted shapes tracked onto wand tips—before being enhanced with extensive interactive lighting and spark and debris elements from our library. One useful piece of show-specific scripting was the creation of a 2D particle emitter in Shake, which could be driven by an audio track for the frozen breath sequences. The soundtrack dialog was used to create a first pass on streams of breath, which could then be individually tweaked for velocity, density, and lifetime to come up with a convincing instance to be comp’d into the shot.

CG supervisor Fred Sundqvist: When it came to 3D, (Autodesk’s) Maya was the bedrock of the pipeline and was used for all of the modeling and animation of CG objects, including the snitch, the horcrux, and the snake with which Bellatrix attacks Greyback. Maya Ocean was also used for the lake in which the Tomb Island stands. Models were textured with a beta version of Mari from The Foundry, and the final scenes were rendered using Mental Ray (from Mental Images). Camera tracking was primarily completed using (Autodesk’s) Matchmover, although (2d3’s) Boujou and (The Pixel Farm’s) PFTrack and PFMatchit were also used on occasion. A few other packages were used in specific instances: The bubbles streaming off Harry underwater were animated in (Side Effects’) Houdini and rendered using the company’s Mantra. The cloudscapes in the final scene are raytraced volumes, lit and rendered using Blender (an open-source program). Maya was also used to create the disapparate spell, for which simple CG models of the characters were created and re-projected with a combination of plate-derived and hand-painted textures. The models were then heavily deformed through keyframe animation, with every limb taking a different route into a central disapparition point. The resulting CG animation was re-sped in Shake to create an effect that crammed a great deal of complex movement into a handful of frames.

One sequence, which called on multiple techniques, was the caravan park the trio pass through as they travel around the country, which has been practically destroyed. The plates were shot on the back lot at Leavesden Studios with just a handful of foreground caravans; Baseblack contributing the rest of the environment. After a texture shoot at a location in Yorkshire, the scene was built up in successive layers inside Nuke, using 2D cards, 2.5 projected objects, texture-projected 3D objects, and, finally, fully lot and textured caravans in Maya.

What was the most difficult part of the work?
Fred Sundqvist: We were lucky that the film generally ran remarkably smoothly. The biggest headache we had was rendering the wings of the snitch. They are supposed to be flapping at 96 beats a second and getting heavy-motion motion blur to work in Mental Ray proved very challenging. Fortunately, the flexibility of our pipeline enabled us to test several different renderers and to use bespoke solutions based on whatever worked for individual shots. We ended up using (DNA Research’s) 3Delight in a number of instances—and all the renders were further helped out with 2D fixes where necessary.

How many people worked on the sequence?
Kate Phillips: Around 30 artists worked on the show in total. We operated with a core crew of 16, with a more or less even split between 2D and 3D, with another six people working in production, editorial, and technical support. We brought in extra specialists, like animators and body trackers, as and when they were needed.

How long did the work take?
Kate Phillips: We started work in earnest in November 2009, and delivered our final shot at the beginning of October 2010. The single longest shot in the show took about seven months of intermittent work to complete—and was then omitted from the final film! We're hoping it might turn up on a DVD at some point.

What other work have you done that you would like to mention?
Stephen Elson: Potter has taken up the majority of our attention over the last year, but we've been able to fit some other work in around it. We looked after the whole of DNA Films' Never Let Me Go for Mark Romanek—around 30 shots in all—which opened the London Film Festival. We have a couple other shows currently in production: We're doing some of the titles on Universal's Paul for Greg Mottola, and around 70 shots on the BBC's Life for Martha Holmes.