The challenge of finger and hand removal (and 3D scanning a donkey)

Behind the scenes with Union VFX on ‘The Banshees of Inisherin’.

If you haven't seen Martin McDonagh's The Banshees of Inisherin, it may be best to stop reading now, since one of the main things discussed in this VFX interview with Union VFX is about their finger and hand removal orchestrated by one of the main characters Colm (Brendan Gleeson) on himself.

Here, visual effects supervisor Simon Hughes discusses the subtleties of that kind of invisible effects work, alongside modern artefacts removal and even the minor VFX augmentation required to deal with animals in the film–and, yep, that included scanning a real donkey.

b&a: One obvious place to start is the missing finger and then fingers. How did you start to approach that one as an effect?

Simon Hughes: Well, there's sometimes a temptation with work like this to just put a green glove on and do it all in post. But that's not really Martin's style and it's not DOP Ben Davis’ style. They’re looking for opportunities to at least get some shots in-camera so they’re not entirely reliant on visual effects.The prosthetics team, led by Dan Martin, were really good at coming up with a couple of options where they suggested different methodologies and then that allowed us to break down the scenes.

So we’d say, ‘Okay, stage one, we’ll do technique A,’ and which would allow us to at least get a selection of shots in-camera with maybe just visual effects having to do a little bit of paint out rather than CG stumps. Then we save up the really big moments for VFX where we bring it close to camera or see it really well.

b&a: When he does wear a glove for the finger or hand, how did this work on set?

Simon Hughes: We did have a green finger sometimes, and we had a glove for where the stump was. It was like a wrap around of flesh, which goes around the base of the real finger, which gives us an edge, which is obviously quite a practical edge that we could work from. It is a good approach, but it did actually pose a few challenges for us because that finger becomes wider than normal. For example, we’ve got the violin playing shots, which were a bit of a challenge. Or we have a shot where he puts his hand on a wall.

To combat this, we scanned the prosthetic and created a CG version of it, which allowed us to manipulate the size. However, it wasn't as easy as we were hoping. We would put that edge in but then the stump looked much larger. Also, if your finger's still there, you get inherent movement in the rest of the area. But if you didn't have a finger there, it wouldn't move as much. So we’d have to fix that movement as well.

Funnily enough, Martin actually quite liked that side of it. One shot made him laugh, where the stump almost looks like a creature of its own. So he decided to keep it in!

b&a: What are the challenges in cleaning up backgrounds for finger removals?

Simon Hughes: There's a lot of rebuilding that's involved. But we were quite lucky in the fact that there were a fair few scenes where Brendan Gleeson was doing quite long speeches and wasn't actually moving a huge amount. So, we were getting multiple takes. We were able to clean plate from either other takes or outtakes, so that was useful.

One challenge is where you’ve got a green finger crossing over your thumb, for example, and you’ve got to recreate part of the thumb. To do that, we had a full CG version of Brendan's hand. We had it as a ‘stage one’ without the stump, and then we had it as ‘stage two’ with all the fingers cut off. This digital version enabled us to recreate some of the areas that were getting obscured by the green finger. Then sometimes just good old-fashioned comp patches and paint work was done to get us over the line.

One other thing with the finger work is just the challenge of roto-anim. That was probably the biggest challenge on the show. Hats off to the roto-anim team here because it's quite tricky getting that movement matched, especially with the challenges of the additional secondary finger movement.

b&a: For the setting of the film, the location, what modern artefacts did you do any clean up on?

Simon Hughes: The location was Inishmore in the Aran Islands and, and Achill Island. They’re both off the west coast of Ireland. The locations were really quite friendly to the shoot, in terms of not having too many modern things to remove. We did have to reduce the amount of buildings a little. When you’re looking at wide vistas and landscapes, there’d be just a few too many. Martin wanted it to feel like a very barren place, just a very small number of thatch hut-type structures and a pub.

For any buildings that remained, it was a combination of either putting a thatch roof on them or some grading work to make it feel a little bit more stone-like. If it was white walls, you’re getting rid of the white walls. If there's any color, you’re getting rid of the color.

b&a: There were some very meaningful, at least to me, helicopter or drone plates with amazing cloud formations. Was there any visual effects intervention in those?

Simon Hughes: That's all plate. The opening and closing shots are two big drone shots. We had to deal a little with architecture on those shots, especially the opening one. You come up over the brow of the hill and reveal the village. There's a few CG buildings in there and smoke from chimneys and all that kind of stuff. But the skies were true to the shoot. They got very lucky.

b&a: Then of course, there's Colm's house being set on fire. What were the conversations about how to shoot some of this for real and where VFX could assist?

Simon Hughes: We did have a lot of discussions with Ben Davis about getting some nice lighting on the roof for the fire. We put a whole light rig on the top of the roof, which was throwing out nice fire lighting. The idea was that once it is on fire, we at least get some proper movement on the ground around the house and you give everyone something to work with. I’m not a believer in cheating lighting unless you really have to.

Then we also had a really good SFX team there. We didn't really want to have to rebuild the whole roof for an SFX shoot, so we just broke it down to about two thirds of the roof, which had some panels which dropped down for when we had to show the collapse. We cut it down to what the minimum height could be and just had enough that we had two-thirds of the roof. We plotted camera positions so that we could cover off an elements shoot, which allowed us to shoot from two camera positions. That allowed enough flexibility to cover all the angles.

We were quite lucky in the fact that they didn't shoot lots of crazy angles and lots of crazy camera moves. Fire is quite flexible. If your angle's not completely perfect, you can kind of warp it into place. But the point being is that when you start setting something on fire, you don't know exactly how many goes you’re going to get at this. We were working in a five-hour window to shoot it in, so we just wanted to have a really minimal setup.

We retained some of the thatch from the cottage. We saved that up when we did the collapse so that at least when the collapse happens, you get some real thatch and that texture. And then all the other shots, we had a fire-retardant fabric, which had a thatch quality to it, and we used those more for the wides. That got us about 80% of the way there and then the rest of it is Houdini FX sims for the fire.

We also did little things like falling embers and extra details just to give it a little bit more texture. Then smoke as well. There's a nice combination of practical and visual effects, which is always my preference if you can make it work.

b&a: I thought there were really great performances from the animals in the film, like Jenny the donkey. Did you need to do any CG animals or splitscreens for the film?

Simon Hughes: We got very, very lucky. We had a couple, nothing too crazy. Actually, one thing we had to do, there were scenes of cows looking through or in windows. We had to take a cow from a different plate and fit it in as Colm's eating his breakfast.

For Jenny, we did actually scan the donkey and had her ready to go as a CG version, just in case. They were worried about when she eats the finger and dies that maybe that would need to be augmented. They didn't know what the prosthetic dead Jenny was going to look like, but again it worked out very well. It still was very fun sorting out a scan of a donkey.