Director of photography Pierre Dejon discusses his work on Just Philippot’s "Acide"

Death from above, by François Reumont, for the AFC

[ English ] [ français ]

What if rain suddenly became deadly ? In the context of global warming, and worries increasing about this upcoming’s summer water reserves, this initial idea holds a meaning of its own.
This is Acide’s take, Just Philippot’s second feature film, screened during the Official Selection, at the Midnight showing, this year, at the Cannes Film Festival. Guillaume Canet plays a divorced father, living under probation with an electronic tagging device, trying to protect his daughter in the midst of a sudden eco-climatic disaster. Pierre Dejon, the film’s director of photography, talks to us about the challenges of such a project, and in particular the difficulty of filming in the rain... when it’s sunny. (FR)

Acide is your first feature film with Just Philippot, although you’ve known each other for some twenty years...

Pierre Dejon : We met as students at the Paris 8 University in Saint-Denis in 2002-2003. This friendship led to several fiction films, documentaries, and music videos, and in 2017 to a short film we shot together, also called Acide, which turned out to be the basis for this feature film. The two films share the same story ; a divorced family forced back together by a natural disaster and having to flee. Of course, the short film was only 15 minutes long, and takes place in a much shorter time unit than the feature. But there are many common elements, notably the idea of Acide rain disrupting their lives. When the producers Yves Darondeau and Clément Renouvin from Bonne Pioche production gave us the green light to make the feature film, it was a rather abysmal piece of work for us compared to the short film. It was a real filmmaking challenge because of the complexities the script posed. We needed to make this "all destroying acid rain" seem real, working with difficult outdoor elements such as fake rain, smoke and melting materials. In this age of digital technology, we wanted to make this world real and believable, with as little CGI as possible and as many on-set effects as we could, in order to immerse the characters into a world on the brink of collapse, but above all, believable.

"Acide" - Photo : Laurent Thurin - Bonne Pioche Cinéma, Pathé Films, Umedia Production Services.
Photo : Laurent Thurin - Bonne Pioche Cinéma, Pathé Films, Umedia Production Services.

How did the preparation go and what challenges were you faced with ?

PD : The film was originally scheduled to be shot between August and September 2021. But for various reasons, filming was postponed by six months. This schedule change had several repercussions, notably giving us more preparation time – useful given the complexity of the project – but on the other hand, having to change seasons, from late summer to early spring...
This decision had serious consequences, as the film takes place for a large part outdoors, sometimes in the woods. The arrival of spring was going to completely change the rendering of this part of the story. Indeed, among our decisions for the visual and artistic direction of the film, Just Philippot and I had the idea of gradually shifting the film into a desaturated universe, with a loss of life and colour as the Acide rain settles over France. With this in mind, the prospect of shooting in autumn seemed better to us in order to take advantage of less lush vegetation, leaves on the ground, and perhaps greyer weather...
To compensate for shooting in spring, we developed a whole strategy in collaboration with the Art Director Gwendal Bescond and then with Thomas Duval, digital special effects supervisor, to completely hide the fact that it was spring when shooting outdoors. For example, in the sequence that precedes the arrival at Deborah’s house, for several hundred metres, we covered the ground on set with dead leaves, wood chips and broken tree branches. All this in the middle of May, in a very spring-like and sunny atmosphere ! We managed to bring to life this late autumn that we had imagined, by also using colour grading to create colour distortions by zone, thus allowing me to completely eliminate the green from certain parts of the image.

Photo : Bonne Pioche Cinéma, Pathé Films, France 3 Cinéma, Canéo Films – 2023

Choosing rain as the main antagonist on a film is rather risky, wouldn’t you say ?

PD : The weather was one of the biggest challenges for us on the film. When you get into a film like this, you’d think that it would be better to shoot in grey weather. At first, we thought that shooting in that kind of weather would help with credibility and facilitate the assembly and colouring between the shots. The VFX team would then add the dark disastrous clouds here and there. When we’d shot our short film, we’d asked ourselves these exact same questions. And just like it was six years ago, – I don’t know if it’s a coincidence –, the weather on set was absolutely glorious. So with that in mind, figuring out how to integrate the sun in a credible way, in a film where rain is meant to fall regularly... We came up with the same strategy as we did for the short film : to place the sun as the central element of the film direction and to build the visual narrative entirely around it. By setting up each exterior scene according to the sun’s position during the day, we chose to place the actors in a setting in which they were always running towards it. This became a conscious sensory take for certain scenes, such as Michal and Selma’s run to the stud farm. Or the scene in the forest before the retreat into the bunker. With Romain Cros, the 1st Assistant Director, we decided the filming order precisely according to the light axis during the day. In order to imagine the sun as both a protagonist in the narrative and a vanishing point for the characters.
Everyone will have their own opinion on the rendering, as it is always peculiar to film rain sequences under the sun, but I must admit that it gave me the contrast I was looking for as the film progressed. The image gets a harder rendering, the rain is better drawn in the image and the visual sensation becomes more violent for the viewer too. But of course this is very subjective.

The film starts with footage filmed on a phone of a trade union demonstration that goes wrong...

PD : This opening was exactly like that in the script. A desire to anchor the film in reality, and to present Michal in his workplace. As the film was shot in chronological order as much as possible, we started the first day of the shoot with this sequence. I think it was important for Guillaume Canet to get into his character. He is a very physical actor, who wants to be as credible as possible in the moment, and the idea of filming everything with mobile phones like in real life contributed to the spontaneity and sincerity of the scene. Together with Just Philippot, we took as a visual reference the documentary film Un pays qui se tient sage by David Dufresne (2020) which, apart from the interviews, is mainly composed of images taken with mobile phones. From a technical point of view, four phones of different brands were used (with the Filmic Pro application) to capture the scene, together with three Go Pro Hero6 cameras and four BOBLOV P100 tactical cameras, like the ones used by police officers on their helmets during interventions.
I suggested to the director that he should also shoot with the main production camera and lenses, as a kind of "security" for the editing, in case filming how we’d imagined it with the phones was not enough. But it was not the case ; Just made this sequence work with these unexpected and realistic images, and I find that it brings a lot to the beginning of the film, and to this punchy introduction.

How did you shoot the rest of the film ?

PD : The vast majority of the film was shot with one camera at a time. Only certain sequences, such as the one in the field at night or on the bridge, where there were a lot of extras, needed extra cameraman and first assistant. I had the pleasure of working again with Olivier Rostan, hired in that role. In addition to working by my side as camera op, he also enriched the film as a B cam operator with several shots that I call "still lifes". Still shots, without actors, with magnificent decors of lifeless elements from our devastated world.
In addition, through a collaboration between our production manager Sacha Guillaume-Bourbault and the RVZ team, I was able to use two cameras throughout the whole film. One was permanently set on a Ronin 2, and the other alternated on sticks or handheld depending on the scene. This configuration allowed me to move very quickly from one setup to another. And to prepare for example car sequences while we were shooting other things. The Ronin 2 is also a tool I appreciate on this type of film, because moving around the sets is not always easy. We couldn’t afford a Steadicam operator , though there were many days when the actors’s movements required it. So I decided to have the Ronin 2 on the whole shoot, which allowed us to use it or not, depending on the fluidity the director wanted to have in the image.
The Ronin 2 can also film certain shots which are difficult to do with a Steadicam. I am thinking for example of the shot where we follow Guillaume Canet running towards the stud farm after leaving the car. While he’s running, he climbs up, then down a hill. This is an extremely complicated shot to do otherwise because there are both face-level and ground-level camera positions in the same shot. Here, my grips Sebastien Demarigny and Simon Brouat had to run with the stabiliser, focusing only on the rhythm of the actor’s frantic race, while I was framing with the Master Wheels, remotely. It’s a device that gives the actor total freedom in their movements. It also offers great framing precision when a close-up is needed while running quickly on a difficult terrain.

Did you have any visual references ?

PD : Although Acide might look like a disaster film, with a standard style from that genre associated with it, our inspiration was rather from Eastern European cinema. One of our main references was Come and See (Requiem pour un Massacre) by Elem Klimov (1985) or The Tribe by Myroslav Slaboshpytskiy (2014) for their style of framing. We were looking for a refined visual look. We wanted to distance ourselves from the expected classic American aesthetic. Despite my personal taste for anamorphic lenses, I wanted to move away from them to find a modern and raw image. A cold image, without the aesthetic distortion of anamorphic.
When we shot the short film, there was also a strong connection with Alan Clarke’s medium-length film Elephant (1989), which itself inspired the title and cinematography of Gus Van Sant’s film. The Steadicam tracking the backs of the characters influenced us a lot. I must also mention Alfonso Cuarón’s Children of Men (2006), cinematographed by Emmanuel Lubezki. For us, there was never any question of shooting Acide in continuous shots, but I particularly like this film in its capacity to immerse us in a great sense of reality, despite the futuristic aspect of the narrative. It was also a real reference in the colour work. I like the hues used and the colour desaturation.
With Just Philippot, we always wanted to stay as close as possible to the characters, shooting most of the time in medium focal length between 40mm, 50mm and 65mm in Full Frame.
The choice of the Full Frame became obvious to me because, paradoxically, a certain part of the film was shot in small spaces, particularly Michal’s car. With the Alexa Mini LF and its Full Frame sensor, I was able to shoot faces with a 40mm instead of a 25mm or a 29mm with a Super 35 sensor. This allowed me to shoot without distorting faces due to the short focal lengths.
With the Zeiss Supreme Prime lenses, which open to an average of T.1.5, we were able to isolate the characters from the background. We wanted to make as few cuts in the action as possible, so we set up a precise framework for the shifts in focus between the characters and their environment. This play with movement only works if very little depth of field is used. Thanks to my first assistant camera Arslan Terrien’s talent, we were free to shoot at very open stops all the time, despite the difficulties due to the characters’ constant movement.

In the second part of the film, the protagonists find refuge in a house, a break in the middle of this endless race...

PD : On this set, the lighting choice was very thought through. The director had a rather drastic take on this : most of the house was no longer powered by electricity, there was no light anywhere, except for a single lamp, bare, used as a kind of candlestick, which could be moved by the characters thanks to a long extension cord. This staging choice therefore forced a break in the way the scenes were lit. There was only one light source and the image’s contrast became very present.
This was a real challenge for me, – in a natural setting where the actors were lit only with this incandescent light bulb –, remaining consistent with light without really cheating. Sometimes a small Astera tube was used on the face to add a shine to the eye and adjust the contrast on the skin, but in the end, apart from a few backgrounds, 90% of the scene was lit only with this light bulb. A very formal choice in the context of the house scenes, shot in Belgium, which served us both for the interiors and for all the exterior scenes.

In this same logic, throughout the film, with the director and the Art Director, we always chose to shoot on natural sets and not to use the studio. It was important for us to confront ourselves with reality. In the car driving sequences with Guillaume Canet and Laetitia Dosch, or on a sequence like the one in the military truck, – in which the characters are shaken around – , we decided to shoot on a real damaged road. The way the bodies and the camera move would never have looked as real if we’d shot this scene in the studio with a truck placed on supports.

The sequence in the mud at night is another challenge...

PD : In this sequence, we shot in a 8000m² field. Once again, the director instructed us to give the impression that the place wasn’t lit. How could we do this while still having to show the action ? Even though the film had a large budget, – we didn’t have the means and cranes of a Hollywood blockbuster with 30m high soft boxes –, so we had to adapt. I was able to install two cherry pickers covering the two main axes of the set, equipped with 12 Luxed LED projectors (to create backlights) in association with Airstar LED structures that we had put in soft boxes (for soft light). My gaffer Mathieu Brémond controlled each source on an Ipad and could change the light intensity.

Le machiniste Simon Brouat
Le machiniste Simon Brouat

One of the staging challenges was to be able to film a character moving continuously through almost 80 meters at night. I was instructed that the light should not interfere with the frame in any way. I like Just’s work because he will always favour his characters’s actions over aesthetics.
With that in mind, we needed to find solutions to make the frame follow such a distance, without cutting, which we managed to do thanks to the possibility to dim the light in real time, keeping a constant T stop on the characters.

You mentioned the film’s progression towards colour loss, how did you manage this on set and in post-production ?

PD : I relied on six LUTs developed with my colourist Raphaëlle Dufosset. This had already been tried out with her six years ago with the short film. The film’s starting point had warm tones, an ’early heat wave’ atmosphere and a certain amount of brightness in the image. As the film progresses, the reds saturation was reduced, especially on the skin tones, then the greens in the vegetation, while the blues remained saturated. Throughout the film, the contrast levels increase progressively. Both in the lighting on the set and in the colour grading. The image becomes harder and colder.

With my DIT, Thomas Briant, present throughout the shoot, we were able to work on additional intensities beyond the basic LUT, and provide the best possible dailies for the edit. With a very advanced colorimetric rendering. Probably even a little too much when I looked at the dailies again. I share this way of working with what Guillaume Deffontaines AFC (whose assistant I was) and Luis Arteaga did on Bruno Dumont’s Ma Loute and Mathieu Vadepied’s Tirailleurs. The LUTs were very thorough during the shoot to establish a very strong formal bias from the start. This also helped the VFX anticipate the final rendering.
After 3 weeks of colour grading at M141 and nearly 200 VFX shots from Digital District, we found the right balance in the chromatic variation built during the film.

(Interview conducted by François Reumont, and translated from French by Chloé Finchet, for the AFC)

Selma, 15, lives in between her two separated parents, Michal and Élise.
Clouds of devastating acid rain are descending upon France.
In a world about to go under, this fractured family will be forced to unite in order to face this climatic catastrophe and escape it the best they can.

  • Watch the short film Acide, by Just Philippot, DP Pierre Dejon :