We’ve written a great deal about 3D on HeyUGuys over the years, much of it has given an insight into the technical aspects of filming in 3D.

Chris Parks of Vision 3 has recently worked on Jack The Giant Killer and Gravity, and has recently spoken at length about the effect 3D can have on an audience. We caught up with him recently, and discussed this, as well as the effect lenses and composition can have on a 3D film.

One of the topics you have spoken previously spoken about is that films have a tendency of ‘not quite getting 3D right’. I’m curious if I can get you to elaborate on that please.

The biggest fear with 3D since Avatar, in this current resurgence – this ‘quality’ resurgence is the accusation of gimmick. All productions are afraid of it, all directors are trying to avoid it, and this has led to the belief that, almost the flatter the 3D, the classier it is – the more it’s setting itself apart from what came before.

This has led to a fear of actually using 3D intelligently, using it to create a sense of volume. It makes it easier if you’re not trying to introduce a lot of depth into something, it makes it easier to create the 3D because you’re not opening yourself up to the same risks, and there’s a curve – ‘the curve of distortion’, as I call it – if you increase the amount of 3D in a subject, it will get better and better and better, and a greater feeling of volume and of roundness and reality, but it will hit a point where, if you take it even a little further, it will drop off. You will become aware of distortion and discomfort, and all the things that you’re trying to avoid with 3D, and the benefits to the story, the narrative of the film will disappear. You will lose that very quickly.

That leads people to work in a much safer area of 3D, where it’s more conservative, you don’t run as much risk of distortion, or of hurting people, and you don’t have to take as much care when you’re doing the depth grade in the edit, or the DI. You don’t have to pay as much attention to the cut or the offline [edit], and in crafting the 3D, and in using the 3D intelligently You don’t need to pace it, you don’t need to treat it with as much care.

Just to clarify, you do native 3D rather than post conversion?

I’m involved in some post conversion, and there is nothing inherently wrong with post-conversion if it’s used in the right way. There are different degrees of post conversion, there are different degrees of native. At the native end, at the DI stage, you’re often working with the image a bit more, and you can pull the best out of the image in the same way you can with colour and exposure and the rest of it. There are elements you can post-convert, you can create effectively native-3D in the VFX, then you can put post-converted elements and native-3D elements on top of it. For me, post-conversion is just another tool for 3D, the bad thing is ill-considered post-conversion, or post-conversion that doesn’t give you better results, or post-conversion that draws the audience’s attention to it, once again pulling you out of the story.

Even if you take a step back as well, and look at the film business as a pragmatic industry, you have a story to tell, you are never going to be able to do everything that you want to do, you’re never going to be able to use all the VFX, or all the cameras, or all the units or all the actors. Even on the most expensive films, there are always going to be compromises, or things you’ll have to use in favour of numbers, and if post-converting some scenes means you can put more time and effort into another native scene, or you can approach things in a better way, or if it helps the director tell more of his story, then it’s completely valid. Approaching it because it makes the workflow easier isn’t, necessarily, that cleverest way to go. The way I like to approach 3D is to look at native and post-conversion as a tool, and make the best use of it.

In my experience, I’ve tended to find most 3D houses tend to do one or the other, for instance Paradise Effects might do the native part of the shoot, but the post conversion work would go to Prime Focus.
The way we set ourselves up is – Paradise come at 3D with rigs, and they’ve got rigs that they want to take out, and shoot film with. Prime focus do post conversion, they offer post conversion as a service. Frame Store do VFX, and stereo VFX, and can offer some conversion, Cinesite can do VFX and post-conversion, and Camera Pace Group have rigs , and they want to go out and shoot native.

We don’t come at it with any of that, we don’t have rigs, we don’t do in-house post-conversion, we don’t have any of the kit that allows us to do that. What we do is support the production to get the best creative results out of 3D. It leaves us free to, if we think that this film or this scene or this shot will be much better if we shoot it native, and not only if we shoot it native, but if we shoot it with a certain type of rig that we can get from Germany or the States, or from wherever it might be, then we’ve got the freedom to do that. If we think that, actually it would be better to post-convert that, while I’m there on set I can be saying, ‘we really shouldn’t be shooting this native. With what we’re trying to achieve in the story, and with the VFX at this point, we’re going to get a much better result, and a much better experience for the audience [with post-conversion]. If we shoot it in 3D, we’re going to throw away the 3D information. Shoot in 2D, post convert it, bring in a different element, and we can get a better result.’

These are a bunch of tools, and I want to have use of all of these tools in order to get the best 3D, and best support the production from a budget and a creative point of view; best support the director, and the DoP and give everybody the best support to help them achieve what they want to do, and I don’t want to be beholden to any particular technology. My background is in technology, and building optics and lenses and cameras to be able to shoot specific things. That’s my background and I’ve done that for fifteen years, particularly in 2D, but in 3D as well. That’s fine when I’m trying to use it to achieve something that nothing out there will do, and we did a production recently where there was nothing out there – no commercially available rigs or optics or cameras that would achieve what we wanted to achieve, so we had a lens system that could achieve something completely different, and we used that.

So you’re neither a DoP or an effects guy. You’re from outside of those backgrounds.

I come at this as a stereo-supervisor, not a stereographer. It’s very much working with the effects house or working with the DoP, working with the director. At its heart, it’s supervising the stereo all the way through, and the VFX house, or the VFX vendors who are providing the effects, I will look after the 3D on that and ensure it’s consistent with the rest of the film. The people doing the post-conversion, Prime Focus, I’m making sure that works with the 3D effects, and the native 3D – bring in the rigs that allow the DoP to put the camera on what he wants, use the lenses that he wants to that give us the 3D that will give the metadata that the VFX supervisor will want for him to be able to create the VFX. I come in as a head of Department, collaborating with everybody else to get the best result.

You spoke earlier about narrative, Obviously there is a perception of 3D as something that doesn’t add narrative. What do you think it adds?

Mark Kermode and Roger Ebert have both talked about what 3D can contribute and what the films out there show can be done with 3D, and their answer is, ‘very little. It really doesn’t contribute to the narrative’. I think in many cases what they’re saying is absolutely right, but the conclusion they’re drawing is wrong. A lot of the films, the majority of the films, arguably, in some ways all of the live action films out there have failed, so far, to really use 3D in the way that it can be.

This was always going to be an evolution anyway, so if 3D’s going to survive, and actually contribute in a narrative way to film, what we’re doing today has to look outdated in a years’ time, in five years’ time, in ten years’ time, we’ve got to be evolving it. In that sense, what has come so far really doesn’t contribute much, but it can do, and it’s starting to, and we’re starting to use it on productions in a way that’s tied to the narrative.
The main thing that I’m trying to do with 3D in a film is to have a form to it, an intelligence to it, a shape to it. It isn’t about framing up a shot, making that shot look the greatest 3D shot it could be, and then moving on to the next shot. And making it the best possible 3D shot that it can be, because you may be putting different parameters on it, which just won’t cut together, and it won’t feel like the same space. If you’re getting desert for every course, you’re not going to appreciate the benefit of it.

It’s no different from what you’d do with colour, or light, or any of the other visual parameters. It’s about changing the mood, and influencing the audience by changing the mood. That can be giving a sense of intimacy to certain shots, and a sense of remoteness to others, and a sense of claustrophobia to others, a sense of contrast between shots, a sense of uniformity or a sense of discordance between shots or sequences, or having a different stereo style for one scene compared to another, having a language to the 3D, so it’s got a different feel and it’s affecting the audience. You can have more specific things – I’ve talked about pulling things close, or pushing stuff further away, that has an effect on scale, and that has a way on the way in which we perceive shots. Part of the difficulty at the moment is that there’s no established language, because audiences are coming to 3D new, filmmakers are using 3D in different ways, it will take a while for these patterns to, these practices to evolve and audiences to evolve an understanding in the same way as they now do with 2D. A lot of the 2D conceits are not absolute; they’re things that have evolved because filmmakers have used them in certain ways, audiences now perceive them in certain ways. The same has to happen, and will happen with 3D.

You mentioned developing a sense of claustrophobia, or remoteness. Let’s, hypothetically say we have a shot in this room, and the camera is set up in one corner. How do you make this room more claustrophobic?

Straight away, we’re making the assumption that we’ve set up the shot, and now we’re going to shoot it, and so how do you set up the 3D camera to make it claustrophobic or not claustrophobic. One should be approaching it much earlier. It comes in conversations about the design of the scenes, the design of the set up, the blocking of the shot, the lighting of the shot, the lens choices. All these things have an effect to how, in this case, you can make the shot feel more claustrophobic, how you can make it feel different to what’s gone before.

For example, the sorts of things you might do, in the shot. You might set up the scene around this table in a pool of light, so it drops off to shade at the edge of the frame. That enables you to pull everything well out into ‘theatre space’. It was used a lot in Hugo. Robert Richardson’s top lighting allowed the edges to drop off into shadow, which meant you could have things sitting out in ‘theatre space’. What I would question is the consistency of the approach there. Often when they were pulling things right out into ‘theatre space’, there wasn’t necessarily a rationale, or the following shot that should have, from a narrative point of view, had the same feel to it. It was then pushed right back. If you light it in that way, you are able to pull stuff out into ‘theatre space’.

You can also, by framing it in the corner away from the window, limiting the depth of the scene, so we can give more volume to the scene that is there. If we open the window, and look out to the sky behind, we need to accommodate the clouds, or the stars, or the sun, or the far buildings into the depth of the screen. By flattening it off, we can just put that on the screen.

Presumably there comes a point where you realise, ‘anything beyond ‘this’ plane is flat’?

You can’t assign depth to different parts of the scene as and how you want it. Your lens choices will affect the depth. If you choose one lens, you will be able to perceive depth in a background building, if you choose another lens, you won’t be able to.

Again, the lighting, which may allow you to use more negative space, and the framing, which may allow you to use more negative space, as you have greater volume in your scene as a whole, which may allow you to maintain some depth int the background. You have this fall-off of depth in the scene. There is a point at which it will fall-off, or it will be too deep, unless you start going a more VFX-route, and shoot green screen. You can shoot background separately, maintain depth in the background, and have depth in the foreground, and you can control it after. That’s something we relatively regularly do. We’re using it at the moment on one production to maintain depth in places where you otherwise wouldn’t see depth.

We’re talking about this from the point of view where we assume the effects of 3D, but have you done any tests on audience members to see their reaction to different ways of producing the image?

When you say it’s better to maintain it, that assumption comes from talking to the director, and what he’s looking to achieve. Absolutely, there are times, there are sequences, there are shots, there are films, where that depth being maintained in the distance irrelevant, it doesn’t matter. There are other times where it does from a narrative point of view. It isn’t an absolute, it certainly isn’t a case where you always want to maintain a feeling of volume or depth in the background, absolutely not. The fact that it flattens out might help you achieve what you want to be achieving with that scene.

It may be that you want to maintain that separation in the background to communicate that a character is in front of another character, or is closer or further away than a character or a building or a car or whatever it is, so you might be using the depth, or the stereo information to separate those. Or you might not be worried about that, in which case you can let it fall-off and be relatively flat. So there are situations where you might want to, but absolutely not categorically.

There is nothing intrinsic in a 3D film that means that any particular shot needs any depth in it at all. There isn’t ‘good 3D’ and ‘bad 3D’, there’s different 3D, and all 3D has a place. People talk about ‘cardboarding’ as bad 3D most of the time. ‘Cardboarding’, which particularly comes from using long lenses, will give unattractive 3D, but used in the right context it can be absolutely right, to act as a contrast to something else. To give a more planar feel to action. If you’re using it creatively, and you’re doing that consciously, then it’s absolutely right.

I was personally disappointed Alice in Wonderland didn’t cardboard more and look a bit like a decoupage picture.

I think there are some tricks that maybe were missed on Alice. The trouble with Cardboarding, as we’re talking about it, is – and people do sometimes look at it and think, ‘ah, Cardboarding. We can use it creatively. This story’s evolved from a comic strip, so it sort of works’, but in order to make it feel intentional, you’ve got to push it so far that it makes shooting impractical. If you’re going to shoot it, you can’t just say, ‘OK, I’m going to bias it towards long lenses because that will make it a bit more ‘cardboard-y’’, you’ve got to actively design your scene so that you can use long lenses, so that you’ve got the volume in there that will create cardboarding, while maintaining the depth, so that it seems intentional. 3D is so much more than just what you’re setting up for the camera, it’s got to be the thinking in the design that runs through the shots that are used in the film.

We’ve been talking about lenses quite a lot, skirting around them, but not being specific. Could you explain how lenses affect 3D, and indeed how 3D may affect the look a lens gives?

Putting it in its simplest and most obtuse form, ‘wide equals good, long equals bad’. If there was one thing I was going to say to you in order to get a nice feeling of depth in your film, it’s ‘stay wide’. Now there’s a question about how wide is wide, and the more you go into it, the more you realise that, actually in many cases in order to get out of it what you’re trying to achieve, going to longer lenses will help you get more of that. For example, if you’re wanting to do a straight forward piece to camera, and you’ve got your interviewee standing in the middle of frame, landscape out behind, and you want to pull them out into theatre space, and give them a good sense of roundness, but not want to distort them, you’re not going to want to stick on your 24mm or 28mm. Actually a 32mm or a 40mm may well give you the best feeling of 3D with what you’re trying to achieve, and allow you to pull them out a bit into theatre space.

Long lenses will often separate out the elements within a scene, so it can make objects look further apart, the opposite to what you will achieve in 2D, where a long lens will actually compress the scene. So 3D will break out the scene into its cardboard flats, separate them with space, and you end up with this theatre flats kind of look, with more distance between them than you would have achieved in 2D. Long lenses can work effectively if you design the scenes as such.

We were shooting the TT for TT3D, and typical motorsport photography on bikes is long lens, with the background all soft and blurry, and a low shot with the front wheel of the bike leaving the road as it comes over the brow of a hill. Long lenses are going to give you cardboard-y, unattractive 3D, unless you design a scene for it, so we scouted out a location where the bikes were coming over the brow of the hill.
We chose a day where the sky was grey, so there were no puffy white clouds, and you could forget about that. So all you had in the scene was just a bit of road in front of the bike, and the bikes coming over the brow of the hill, high speed, on a 560mm lens; the two cameras separated by about 18 inches, and we were able to maintain volume – the opposite of cardboarding – in the bikes, despite the fact that we were on the long lens. We were creating that typical motorbike, motorsport photography feel. There are always ways around it, and there’s no categorical choice. You need to use them creatively, you need to use them with the knowledge of what you want to achieve with a particular shot.

Presumably things like inter-ocular distance and point of convergence are going to be important for this too.

The key point is, if you go for a longer lens, you need to have a wider inter-axial, a wider separation between cameras if you want to maintain volume in the subject. If I had you filling the frame, on a wide angle lens, I would need an inter-axial of ‘x’. If i had the same framing of you on a lens twice the focal length, I will want to go to ‘2x’ on the inter-axial in order to maintain the same volume. It does more to the audience’s perception of the shot than that, and it changes your relationship to your background, but there is a fundamental [relationship] that you are changing your inter-axials based on your lenses.