Prime Focus' London and India Locations Collaborate on over 1,500 VFX Shots

Creating the visual effects for the feature film Tales of the Riverbank, based off the popular 1960s British television series, required complex compositing of furry puppets shot on bluescreen, some CG set extension and characters and an intensive DI, all coordinated by Prime Focus London and its Indian sister companies in Mumbai, Chennai, Hyderabad and Parel.

We spoke with VFX supervisor Derek Moore about the creative workflow and coordinating if all between London and India.

Click below to see a sampling of the VFX work on Tales of the Riverbank.

Talk about the decision to shoot most of this film involving taking animals live as opposed to creating it in CG.
There’s a certain quality to real puppets. This is aimed at kids of course so the reality of a real talking puppet is somehow more charming than a computer generated image. We could have done it CG but having the puppets added a certain level of humanity to it that wouldn’t come across in CG.

We shot a lot of the backgrounds and bluescreen with puppeteers and we had to put the two together to make it look as real as possible. If you go the CG route on that you’re into a Pixar-type Toy Story film, which is great if the story fits but in this case it was the charm of the animals that is the carrying narrative.

How did you handle the composite of the puppets and the backgrounds?
Keying furry animals against bluescreen is notoriously difficult because the edges of the fur are very fine. It was shot on HDCAM, which is slightly compressed so there were some issue there. We eventually found keying methods that worked for us and we spread those methods across the group. We had a mixture of keying methods but generally Primatte on eyeon Fusion with some preset setups that we saved. There was some Flame work for the more difficult composites. It took a while to look good because there was a lot of fringing and ringing that you normally get was quite hard to remove. When you are dealing with that number of shots it’s easy for one experienced keyer to nail it but when you have to roll it out to a lot of artists it can be a challenge.

What other cleanup and CG work did you have to do?
There was only a little CG work. The character of the Owl and the flea, as well as the interior of the factory (created in SoftimageXSI). Then there were some set extensions and the CG marmalade, for which we used RealFlow.

Obviously the puppeteer and rod removal had to be by hand. There were moments when the rods that control the arms and legs would pass in front of the character so we have to patch bits of the fur. That was tricky because fur is an unforgiving material to work with in post, it has to join perfectly. Hair is quite difficult to replicate so it took a lot of hand panting and work by a lot of people to remove all signs of the puppeteers. Once all the keying and comps were done we brought it into Smoke to see how it fit together.

With all these different elements going on at different location that made the DI fairly intensive.
The grade was pretty tricky because with so many shots comped together there was a lot of discontinuity in the compositing process so there was a lot of balancing that needed to be done. It wasn’t like we could have one artist leading a sequence of the same environment. The same environment cropped up so many times and so many people were working on it that we ended up just making the decision to try and match the foreground to the background plate that was chosen and then the inevitable inconsistencies in the background plates once the foregrounds were comped would have to be balanced. We used Lustre for the grade. Then the final grade added a golden dreamy look to the whole film.

What was the methodology for deciding what shots were handled in London anwhich ones went to the India facilities?
This was the first project that had such a large scale of working with India. We were learning little as we went along. It started off with us thinking that we would just keep the most difficult shots here in London and pass off some of the simpler tasks to India. What ended up happening is we kept the CG stuff here and India did most of the other work. They did 1,200 of the 1,500 VFX shots.

How was the data transferred?
To get data to them, when there was a lot of data we’d put it on a hard drive and send it on an airplane because that is the quickest way to deliver that amount of footage at the moment. Otherwise it was up and down via ftp. Or we’d put shots on a DVD, which allows you to bypass customs and it comes the next day.

And how was all the work tracked and coordinated?
We had a producer in each of the facilities in India who would have an allocation of sequences. Ideally we kept sequences in one facility so there was some level of consistency. The lead producer in each facility allocated the work to the artists.

In London we kept a master database of who was working on what so we had an idea of where we were in the project. The creative was quite impressive. Once we nailed the keying issue the discussions about the creative between here an India was very good and they were receptive to changes that had to be made.

Key to all of this was we sent one of our lead Flame artist Ben Murray over there to do VFX supervision of the India work, so when we had issues with particularly complicated shots we’d sit down remotely with Cinesync using Skype and chat about particular shots, drawing on the picture so that each of us knew what we were going for and then he could sit down directly with the artists and implement the direction that I’d given him. So that eliminated a lot of the potential communication issues, which had cropped up in the past when I’d talk to a producer in India where they would understand the basics of what I’m going for but the subtle nuances sometimes can take a long time to explain. So having Ben there to implement and oversee the changes helped a lot.

Credits:
Post Production: Prime Focus London (PFL)
VFX Supervisor: Derek Moore
VFX Producer: Pierre Fletcher
CG Supervisor: John Harvey
2D Supervisor (India): Ben Murray
DI Supervisor: David Clarke
DI Artist: Simon Bourne
Production Company: Riverbank the Movie
Director: John Henderson
Producer: Peter Watson-Wood
Voices: Jim Broadbent, Steve Coogan, Stephen Fry, Ardal O'Hanlon, Peter
Serafinowicz, Morwenna Banks, Amanda Hart
Writers: Andrew Hislop, John Henderson
Puppets: Asylum Models