Behind the cinematography with iPhones, drone work and VFX in 28 Years Later. An excerpt from issue #63 of befores & afters magazine.
28 Years Later was primarily filmed using iPhone 15 Pro Max phones. A range of action cameras, drones and other cameras were also relied upon. Blackmagic Design’s Blackmagic Camera app for the iPhone was part of the shooting process, too.
DOP Anthony Dod Mantle shot in 2.76:1 aspect ratio after initially intending to shoot in 1:2.39. “Despite the unusual image capture mode and toolset, we felt the 1:2.39 certainly protected our idea of delivering a widescreen theatrical release experience on the cinema screen,” Dod Mantle told befores & afters. “Five weeks into camera tech prep, I noted that there was more real estate on the iPhone sensor at each side to be had due to the way we were capturing the image. I did not want to waste this and also thought the 2.76 experience might add to the provocation as well as enhance the loneliness of the few actors we generally had in the frame in the vast landscapes we intended to create. We recorded a comparison check test and screened this for Danny and he agreed immediately, which was great for the film.”
Dod Mantle famously relied upon a Canon XL-1 digital camcorder on 28 Days Later, aiding in giving that film its gritty feel. On 28 Years Later, iPhones and small digital cameras served a similar purpose. Firstly, however, they had to be ‘hacked’ to allow for a level of control of the image.
“In essence,” outlines Dod Mantle, “hacking into any iPhone in a reliable manner requires deep knowledge of the science within the gadget. To attain this kind of information—usually heavily protected by NDA clauses—requires collaboration and acceptance by or with an organization like Apple. Just poking around for details of their image science could be parallelled to banging on the gates of a Scottish whisky distillery at 3am asking for a recipe. There is a very high degree of protection and secrecy to a great deal of the technical and scientific formulae relating to high end technical gadgetry today.”
“So,” continues Dod Mantle, “we were more bound on informing Apple and the Blackmagic team of our escapades, ambitions and suchlike in an attempt to help them understand some of the more challenging technical issues we were facing to secure the level of imaging we were seeking to achieve without unnecessary upheavals along the way. This was either in the practical recording stage as well as the post flow stage regarding editorial and all the VFX work looming ahead for our friends at Union to address. Both the Apple and Blackmagic teams were consistently supportive from day one, throughout.”
Via conference calls between Dod Mantle, his camera and DIT crew, visual effects supervisor Adam Gascoyne, Apple and Blackmagic during prep, Dod Mantle says “our mutual and singular ambition was to entertain and eradicate as many problems as we could prior to shooting. I would say these key concerns evolved around image stabilizing settings and solutions within the camera settings internally and externally. This was largely due to Danny wanting a flexible moving camera most of the time. We were striving to protect the reality of an ever growing VFX event list that would have dire economic and technical consequences if we recorded the material at random settings within the iPhone and Blackmagic app. The conversion of Apple log to ARRI log was another issue for editorial workflow as well as controlled image monitoring on set.”
During the shoot, Dod Mantle made certain adjustments in the shutter settings and frame rates in an attempt to replicate what he cites as the “now historic shutter language of 28 Days Later, but in our own new way. Basically, ‘artefacts‘ to most of us is officially a dirty word as suggested it threatens the reliability of the normal accepted image. There are so many variations of artefacts related to image capture systems that it is impossible to generalize and even more hopeless to seek agreement across the brethren of filmmakers. I personally embrace many artefacts relating to glass lens optics depending on the nature of the scene and the type of story to be told. It is all part of a longer process in film production and in the case of the image capture to the post VFX stage. The uncontrollable artefacts within the technology of the phone itself were the biggest enemy in general, except for certain looks related to the multi-bar cam [see more on this, below] imaging idea that was developing on the go throughout shooting and well into the editorial stage where Danny and Adam at Union were still exploring ideas that did seem to incorporate certain digital artefacts that were pleasing to some!”
Dod Mantle’s intention for the photography with iPhones and other small cameras was always to be flexible and agile. Indeed, scenes were often ‘on the move’ for both interior and exterior shots. Still, the DOP needed to deal with stabilization, just like any film project. “Danny wanted no camera tracks or heavier grip solutions on any exterior location because of the inevitable damage to the surfaces, where the intention was to take advantage of overgrown natural terrain as if it was an unspoiled world 28 years after civilization was more or less extinct. Therefore, a system of image stabilization was going to be essential. In-camera phone stabilization was a big no due to consequent artefacts embedded in the image. I had to ascertain the character and style of camera movement most appropriate for Danny. He did not want the horizon to bump off level as in conventional hand-held. The most simple of stabilizer methods such as ‘blogger’-like pole systems are light and quick but lack precision and speed for dramatic operating and positioning in relation to actors.”
“Steadi-cams were also not really wished for by the director as he preferred me to be on the camera whenever possible,” adds Dod Mantle. “We then started to explore DJI Ronin systems hand-in-hand with me hunting the correct weight and ergonomical glass to fit our assumed focal length needs. This was teasing because some directorial ideas were continually evolving during prep and even far into shooting. I was also looking at both spherical and anamorphic primes. Then a zoom had to be found for some shots. It became a mix of Ronin stabilizing systems with three axis hands on as well as remote control for running shots. No in-camera stabilization ever took place except occasionally on a telescope system occasionally attached to the phone on tripods.”
Visual effects studios are, of course, typically used to receiving plates shot with cinema cameras, either film cameras or on common digital platforms such as the ARRI ALEXA or a RED camera. Union had on several previous Boyle and Dod Mantle productions already had experience with a variety of other camera platforms (for example the SI-2K used on 127 Hours). That meant, shares Gascoyne, “we weren’t too worried about the color pipeline with the iPhones. And, actually, it was fairly good. There were a few little issues with it being 4:2:0 rather than 4:4:4. I mean, I wouldn’t put it near a bluescreen again, that’s for sure. But we did a lot of gray screens actually, and it coped a lot better with those.”
What Gascoyne did research early on was any of the in-built internal stabilization on the iPhone. “This would have meant we couldn’t do any camera tracking, so we were trying to work out ways of extracting what the phone was doing to the image in order to stabilize it so we didn’t have to switch it off. In the end, we had to switch off the internal stabilization so we could camera track anything that had any CG going into it. In an ideal world, we would’ve been able to reverse engineer the stabilization, that is, remove it, do our camera tracking everything, and then reapply it.”
Union would, in visual effects shots, replicate some of the vignetting on the images that came from Dod Mantle utilizing vintage lenses that had been Jerry-rigged to the phones. “They made things a little blurry around the edges and gave the frame an amazing look, so we had to match those,” details Gascoyne. “Obviously if we’re comp’ing into those or trying to replicate the shots that are cut around it, then that’s something we had to do a bit of ‘lensbaby’ matching to. Meanwhile, we were matching the grain structure and everything like that as well. Well, it was not really grain, but we came up with ways of replicating what the phone does to the images in terms of the compression artifacts and everything.”
To achieve a very specific kind of effect during the film, a camera board array system fitted with between eight and 20 iPhones was devised, allowing for shots to be filmed from multiple angles simultaneously. “The array system was a big exploration and number one request from Danny,” recounts Dod Mantle. “We agreed to develop a more hand-held potential eight cam rig as well as a 20 camera rig. It took time from drawing and conception through to physical testing and adaptation. The physics were complicated to secure speed and manoeuvring combined with a robust support system that could be relied upon. Terry Williams and David Reeves from my grip department led the process from ergonomic design through to completion.”
Experimentation with the array occurred even during shooting. “This often happens when developing an idea with a director like Danny,” states Dod Mantle. “He continues to see new possibilities as the idea evolves into its own reality! We had hand-held situations and more precise static set-ups, and we threw it around a bit when we could in scenes evoking violence. We succeeded in attaching it to Technocranes, too, in the causeway sequence shot in a studio. The technical setting up for precise exposure settings did prove challenging at times as we initially could not apply any kind of slave control system until very late on in a beta attempt. Since our production, this has got better due to manufacturing a system to facilitate multi-phone cam operation.”
Union had been involved with camera array rigs on Danny Boyle films previously. “It stems back a little to the camera trickery on Slumdog Millionaire where we used the Canon cameras and did very fast shutter repeat still images, which gives you this amazing high resolution,” recounts Gascoyne. “Danny’s always liked to use these little tricks just to pop the audience into a more visual place for certain elements of the films. During Pistol, we talked a lot about building what he called ‘a poor man’s bullet time rig’, where we set up a load of cameras and none of them are quite aligned in the way that you would if you were building a proper bullet time rig.”
The array found use in a variety of instances. For example, when an Alpha infected is shot by an arrow, the rig was utilized to bring a visceral feel to the arrow impact. Another was when the Alpha Samson rips off a soldier’s head. For these shots, Union would stitch the multi-plate footage gathered from the rig together, adding in any CG elements—such as an arrow—where necessary.
“What we tried to do was make an array that was visual effects free, to an extent,” adds Gascoyne. “We would stitch the footage together and that might be the shot. Or there could be other shots where we then put in the CG arrows. The blood was often all real. The idea was that you could run this thing and if it had no CG arrow in it or anything, it would be standalone.”
One particular moment involved the ill Isla (Jodie Comer) being told by her husband Jamie (Aaron Taylor-Johnson) that their son Spike (Alfie Williams) was being taken to the mainland. “She reacts quite badly to that, even though she’s already been told, and it’s a demonstration of her slowly losing her mind,” outlines Gascoyne. “When she shouts at Jamie, the array shows that from 10 different camera perspectives. We took the array up there and got her to scream into it several times. I don’t know what the neighbors thought!”
To deal with stitching shots, Union matched and synchronized the footage. “The bar cam arrays did bring some challenges in VFX,” explains Union DFX supervisor Dillan Nicholls. “We needed to line up and sync 20-plus cameras in matchmove, and ensure continuity across VFX work from each angle. Matching and sync’ing these in post meant solving issues around chroma subsampling, stabilization artifacts, clipped highlights and unrecorded focus shifts. It was a really great piece of kit, and a lot of fun to use. When you see the blood from when the arrows hit, I think it really does do what we set out to do, which was capture the gore.”
A significant number of shots in the film were realized with drones, including FPV drones. “I was a big fan of FPV drones from the outset of this film,” sets out Dod Mantle. “Whilst I totally acknowledged the use of traditional drone cameras for high panorama work both interior and exterior, I really wanted to explore a more dramatically disciplined FPV operating as if the lens was much closer and more directly engaged within the drama, as opposed to outside or above as a gliding neutral spectator. Both became necessary and effective, but I felt mostly stimulated by the physical bravery and intensity of the FPV.”
Drone operator Peter Keith was responsible for the drone shoots on the film, which included this FPV work. He mentions that one reason drone shooting came about was to echo the small footprint that Boyle and Dod Mantle had established with smaller cameras. “The film is all set in an overgrown wilderness and they didn’t want to have a crew trampling down on the landscape,” observes Keith. “The other thing was being able to establish these two small figures, whether it’s the father and the son, or the mother and the son. It was great to be able to get some pristine shots of that landscape that they’re in and be quite quick about it as well.”
The drone team was a group of three—Keith as pilot, camera operator Robbie Jones and first assistant camera operator Joseph Dixon Tsitsikas—who worked with main unit, second unit and sometimes as a splinter unit.
In terms of drone equipment, Keith was asked early on by Dod Mantle whether iPhones could be something that could be flown. “I thought, how do I get an iPhone up in the air? I wondered, how do you control exposure when you’re flying around and suddenly you’re looking at the sun, and then you’re not looking at the sun, or you’re flying into a forest? What a nightmare to try and think of all that! However, I did some experimenting at home. I’d done some small drone FPV work. I put my iPhone onto this and flew it around the house. I sent a clip of the footage over and said, ‘Is that the kind of thing you’re looking for?’”
The footage was promising, but it was not the typical kind of drone footage that Keith was used to acquiring. “With the iPhone shoot, your camera’s bolted to the front of the FPV drone and the frame is fixed. And so if you want to fly forward, the frame tilts down and then you brake, and the frame tilts up if you roll left or right. That’s much less like a crane than the DJI Inspire 3, which I had mainly used, would be. And so we realized it was just going to be too tricky to get the iPhone onto a system that would offer flexibility and flight time. We could always get a heavy lift drone in to mount an iPhone, or a rolling gimbal underneath it and mount the iPhone and then the adapted lenses, but the thought was to stay comfortable with the Inspire and use that and the flexibility of the lenses, the focus control, and the iris control.”
“Anthony said, ‘I want you to be able to fly close and safely to the actors and if you can’t do that, if you’re having to fly a heavy lift drone with an iPhone on it and adapted lenses with short flight times, and you can’t get close to the actors, then don’t worry,’” adds Keith. “He said, ‘I want you to be here right amongst it.’”
Some of Keith’s drone highlights on 28 Years Later included a shot of Jamie running out of the gates of the island onto the causeway. “Anthony said, ‘Right, I want you to fly a foot over the water and just go full speed in towards Aaron Taylor-Johnson, coming up to a close-up of Aaron as he’s running in. Joe and Robbie did a very good job at operating, and pulling sharps over water, because there’s no indicators as to how close you get.”
Another favorite shot involved a chase sequence where Spike and Jamie see an Alpha for the first time, and a range of other infected running down a hill towards them. “That’s when we first started using the FPV drone, which just had a GoPro on it. This allowed you to get very quite close to the action. In that sequence, too, it moves on into the woods, and there’s a clearing. I had the FPV goggles on. It took a few goes because it was a very tight clearing. It was so nice to see some of these shots in trailers for the film and in the film itself. It was very rewarding.”
