Prime Focus 3D Exclusive

As 3DFocus.co.uk announced last week, the 2D – 3D conversion of Star Wars was completed by Prime Focus, a VFX company who were responsible for some conversion work on Avatar, the Clash of the Titans conversion and Chronicles of Narnia as well as conversion work on Judge Dredd 3D.

Head of Production Matthew Bristowe speaks exclusively to 3D news website 3D Focus about his surprise at still having to defend the work on Clash of the Titans, their plans for television back catalogue conversion and the painstaking processes behind 2D to 3D conversion.

 

3DF: How did Prime Focus get involved with 2D – 3D conversion?

The first 3D project we took on was the visual effects on the film Journey To The Centre Of The Earth. On the back of that along came Avatar. The Prime Focus R&D department working on Avatar put a lot of research into solving the problem of how we could deal with left and right discrepancies which essentially evolved into how could we create one eye from another eye and this evolved into conversion.

3DF: Prime Focus took a lot of criticism over the conversion of Clash of the Titans. Do you regret taking on the job of Clash of the Titans when you had so little time to complete the conversion and there were reviews like "the first film to actually be made worse by being in 3D."?

Here is the deal with Clash of the Titans. I am still surprised that, here we are, a year down the line and it is something we are still either having to defend or discuss. It does take up a large part of what we do.

From a technical point of view with have moved on massively. From a quality point of view, we have also taken huge leaps and bounds. We are very comfortable with the work we did on Clash of the Titans. We developed a solution where we could create a left and right eye from mono plates. We presented that to Warner Brothers and then the work began on Clash of the Titans. Warner Brothers saw it as a great opportunity to convert a film they were currently working on and it was an incredible opportunity for us to really build the pipeline and learn a huge amount as well.

So much has changed from what we have learnt on that going forward to other shows but Clash of the Titans set us on the road and it placed us two years ahead of our competitors. It has been fantastic for us.

3DF: Did you feel the criticism of the Clash of the Titans was unfair when people did not understand the time pressure involved?

It shows what an ambitious and forward thinking company Prime Focus is. We took that on knowing what we were getting involved in but also not knowing to a certain degree. It is mind blowing how much data and sheer hard work that went into that.

There are no regrets – it was great for us. We did what we did in the time that was available to us. We delivered the film on time which, for a lot of clients, is just as important as providing great quality. There is no point in having wonderful images and beautiful quality if you’re not going to deliver and other vendors have suffered because of that – you have to deliver a show, that’s what it is all about.

The film satisfied the Director and the studio. We have a great relationship with Warner Brothers and they also recognised what we achieved in the time and that further down the line this is only going to improve.

3DF: Clash of the Titans was not filmed with conversion in mind. Do you think your future projects will incorporate the conversion planning in the pre-production process and how does this affect the quality of the outcome?

It affects the quality hugely. Conversion planning upfront is something we promote and are actively involved in. We have production staff and creative staff on set of current films who supervise the filming with 2D to 3D conversion in mind as a visual effects supervisor representing a facility would do on a big film. We are able to provide technical and creative support for a show upfront in pre-production, through production and then into post production to achieve a much better quality of 3D.

3DF: How far into the pre-production or production was it decided that Chronicles of Narnia was to be converted to 3D?

Principle photography had finished but visual effects had yet to be done. We got involved with guys like Walden Media, Sean Santiago, stereographer Ed Marsh and the rest of the 3D team at a very early stage so when we did turn over the production, a lot of the decisions had already been made. A depth map had already been laid out and created but fortunately Prime Focus offers a very interactive, iterative, intuitive process so even though certain depth decisions were made upfront we have a very flexible system to be able to change depth decisions, re-review and return shots which could be within a day; it is that quick.

It worked really well. It recently won an award at the International 3D Society for best live action 3D film. We are constantly pushing the work. Our team of artists who we put together in London post clash and prior to Narnia, have developed a new industry technique. We’ve trained them and, after working on a number of very big projects, they have grown over time.

We talked about the quality of Clash of the Titans before but compare that to the quality now and our artists are so much more experienced and so much more skilled, particularly in 3D.

3DF: Many people can’t get their head around the fact (including me!) that you need to recreate image data that would have normally been produced by a second camera which does not exist. How, in principle can you do that? I have heard of something called in-painting – is this the technique Prime Focus uses?

A lot of it is a secret of course. At Prime Focus we use a large array of techniques and they are mainly developed in house. As other vendors have found early on, no single technique can meet all the challenges so we have crafted many proprietary techniques. We can’t talk openly about them; You will have to come and work for me and train as an artist!

3DF: I have read that when converting people to 3D, not only does their outline have to be rotoscoped but individual elements of their body have to be rotoscoped to prevent them looking like cardboard cut outs. This must be mind blowingly detailed and time intensive. Is this a frame by frame manual process?

It is a frame by frame manual process. These rotoscope artists are highly skilled.  Super tight quality roto is the key to the success of this. In a single frame we pretty much roto everything. You could have hundreds of different roto elements within each individual frame and that allows us to sculpt the shot to get genuine volume and depth within it. For a single character we don’t just cut out the outline of the face; we rotoscope the eyes, ears, nose, lips etc. so we can generate a really high quality volume of depth which is not necessarily achievable when shooting native stereo. By having greater control of all the elements within a shot we have greater control of the 3D quality.

3DF: Would you even have to rotoscope individual strands of hair?

Yes – in order to separate the foreground character with hair from the background you would have to do that. I have to say it is not all in the rotoscope; we’ve got other skills and techniques for doing that . The View-D artists are highly trained, highly talented individuals and extracting a single strand of hair from a background is a very skilled job.

3DF: What does volumising mean in the 3D conversion world?

To sculpt depth into objects and characters as opposed to planes and geometry. Planes and geometry implies you have got a ground plane, wall or distinct areas to give you depth where as volumising is about giving shape to a face or arm for example.

NEXT PAGE – Dispartiy maps, back converting television programmes, conversion work on Avatar and View-D