Astera Titan Tubes seem to be everywhere at the moment, every gaffer and DP’s favourite tool. Resembling fluorescent tubes, Asteras are wireless, flicker-free LED batons comprised of 16 pixels which can be individually coloured, flashed and programmed from an app to produce a range of effects.
Here are five ways in which I used Titan Tubes on my most recent feature, Hamlet. I’m not being sponsored by Astera to write this. I just know that loads of people out there are using them and I thought it would be interesting to share my own experiences.
1. Substitute fluorescents
We had a lot of scenes with pre-existing practical fluorescents in them. Sometimes we gelled these with ND or a colour to get the look we wanted, but other times it was easier to remove the fluorescent tube and cable-tie an Astera into the housing. As long as the camera didn’t get too close you were never going to see the ties, and the light could now be altered with the tap of an app.
On other occasions, when we moved in for close-ups, the real fluorescents weren’t in an ideal position, so we would supplement or replace them with an Astera on a stand and match the colour.
2. Hidden behind corners
Orientated vertically, Asteras are easy to hide behind pillars and doorways. One of the rooms we shot in had quite a dark doorway into a narrow corridor. There was just enough space to put in a vertical pole-cat with a tube on it which would light up characters standing in the doorway without it being seen by the camera.
3. Eye light
Ben Millar, Hamlet‘s gaffer, frequently lay an Astera on the floor to simulate a bit of floor bounce and put a sparkle in the talent’s eye. On other occasions when our key light was coming in at a very sidey angle, we would put an Astera in a more frontal position, to ping the eyes again and to wrap the side light very slightly.
4. rigged to the ceiling
We had a scene in a bathroom that was all white tiles. It looked very flat with the extant overhead light on. Our solution was to put up a couple of pole-cats, at the tops of the two walls that the camera would be facing most, and hang Asteras horizontally from them. Being tubes they have a low profile so it wasn’t hard to keep them out of the top of frame. We put honeycombs on them and the result was that we always had soft, wrappy backlight with minimal illumination of the bright white tiles.
5. Special effects
One of the most powerful things about Titan Tubes is that you can programme them with your own special effects. When we needed a Northern Lights effect, best boy Connor Adams researched the phenomenon and programmed a pattern of shifting greens into two tubes rigged above the set.
On War of the Worlds in 2019 we used the Asteras’ emergency lights preset to pick up some close-ups which were meant to have a police car just out of shot.
Back in February 2019 I spent a long day in Black Park, a forest behind Pinewood Studio, shooting a short film called Alder for director Vanda Ladeira. A little late perhaps, but here are my reflections on the cinematography and general experience of making this experimental fairytale.
The film is about a forager (Odne Stenseth) who does not realise he is being watched by the very spirit of the forest, the titular Alder (Libby Welsh). As he cuts a sprig of holly, or steps on a mushroom, he is unknowingly causing her pain. Meanwhile a group of ghosts – Alder’s former victims? – cavort in the woodland, and strips of film made with ground-up human bone reach out from the trees to ensnare the forager.
Vanda contacted me after seeing my work on Ren: The Girl with the Mark. She was keen for Alder’s lair to have the same feel as Karn’s house in that series. We had a number of meetings to discuss the tone, visuals and the logistics of the shoot, which initially was going to take place over two days but was eventually compressed to one.
In October 2018 we conducted a recce in a forest that we ultimately weren’t able to use. I remember at the time that I was considering shooting the project on celluloid, tying in with the plot point about Alder making film from her victims’ bones. I dropped the idea after taking light readings on that recce – when it was very overcast – and realising just how dark it could be under the tree canopy.
We ultimately shot on a Blackmagic Ursa Mini and Xeen primes, provided along with the lighting kit by gaffer Jeremy Dawson. The Blackmagic sensors seem to do very well with earthy tones, as I noticed on the village set of Ren, and the Ursa rendered the browns of the bracken, the soil and the forager’s costume nicely. Jeremy also provided us with a jib which enabled us to underscore the forager’s action with some definite moves: an introductory crane down; a dramatic pull up as he drives his knife into a tree; and a frantic boom down with him as he searches for his lost compass. In Alder’s lair we kept the camera drifting from side to side or up and down to bring energy to her more static scenes.
Lighting for the forager’s scenes was all natural, with just a little bounce or negative fill from time to time to keep some shape to the image. An Artem smoke gun, operated by Claire Finn, was used on almost every shot to give the forest some life and mystery, and also to keep the backgrounds from getting too busy; the grey wall of smoke serves to fade the background slightly, keeping the eye focused on the foreground action.
As there was no dialogue, I was free to change the frame rate expressively. Examples include: over-cranking close-ups of the forager’s feet and hands in contact with nature, emphasing the sensuality of his unwitting connection to Alder; over-cranking the dance of the ghosts to make their movements even more beautiful and supernatural; and under-cranking the forager slightly to enhance his panic when he finds himself lost and surrounded.
Alder’s lair was a set built by Denisa Dumitrescu in the forest. I took broadly the same approach to lighting it as I had for the reference scene from Ren, making some holes in the branch-covered roof and shining a blinder (a bank of four LED spotlights) through it to produce dappled shafts of sunlight. On the floor around Alder were a number of candles; we beefed up the light from these by skipping an 800W tungsten lamp off a bounce board on the floor.
The biggest challenge was the meeting between the two main characters, a scene scripted for daylight which we were forced to shoot after dark due to running behind schedule. It was the longest and most important scene in the film and suddenly the cinematography had to be completely improvised. We did not have anywhere near the lighting package that a woodland night exterior normally calls for – just 800W tungsten lamps, a few LED fixtures, and a generator only powerful enough to run one of each.
What I ended up doing was putting an 800 in the background, ostensibly as a setting sun, and bouncing a blinder off poly-board as fill. We shot the whole scene through in a single handheld shot, once with smoke and once without, then picked up a few close-ups.I tried to hide the lack of light in the background by allowing the 800 to flare the lens and render the smoke almost impenetrable at times. Vanda and her editor, Tom Chandler, leant into the strange, stylised look and bravely intercut the smoky and smokeless takes. The result is much more magical and expressive than what we would have shot if we had still had daylight.
You can watch the finished film here. It won me Best Cinematographer at the New York Cinematography Awards (August 2019) and Film Craft Award: Cinematography at Play Short International Film Awards (2019).
In August 2019 Jonnie Howard, director of The Knowledge, approached me about shooting an unusual short film with him. A Cliché for the End of the World is only two minutes long, but Jonnie wanted to shoot it as two unbroken takes which would be presented side by side. Each take would follow one character, starting and ending with them next to each other, but separating in the middle.
My first thought was that the two takes would have to be shot concurrently, but to squeeze two cameras into the small location and keep each out of the other’s frame would have been impossible. Instead, we settled on shooting with a single camera. After capturing 18 takes of the first side, Jonnie reviewed the footage with his editor Kat and selected one to use. We then shot the other side, with Kat calling out cues that would keep the actors in sync with the selected “master” take. (It took 18 takes to get this side in the can as well, partly because of getting the cues right and partly because of the difficulties Steadicam op Luke Oliver had in manoeuvring up the narrow staircase.)
The film had to be lit in a way that worked for both sides, with the camera starting in the living room looking towards the kitchen, moving up the stairs, through the landing and into the bedroom.
Working as usual to the general principle of lighting from the back, I set up a 2.5K HMI outside the kitchen window to punch a shaft of sunlight into the room. I angled this steeply so that it would not reach the actors directly, but instead bounce off the floor and light them indirectly. (See my article on lighting through windows.)
Gaffer Jeremy Dawson blacked out the living room windows to keep the foreground dark. He used an LED panel set to 6,600K (versus our camera’s white balance of 5,600K) to simulate an off-screen TV, waving a piece of black wrap in front of it to create dynamics.
Next we needed to bring up the light levels for the actor’s journey up the stairs, which were naturally darker. Jeremy and spark Gareth Neal opened the loft hatch on the landing and rigged an LED Dedo inside, aimed at the darkest part of the staircase. They diffused this with some kind of net curtain I think.
To brighten the landing we set up a diffused 2×4 Kino Flo in the spare room and partially closed the door to give the light some shape. Both this and the loft Dedo were a couple of stops under key so as not to look too artificial.
All that remained was the bedroom. The characters were to end up sitting on the bed facing the window. Originally the camera in both takes was to finish facing them, with the window behind it, but this would have meant shadowing the actors, not to mention that space between the bed and the window was very limited. After some discussion between me, Jonnie, Luke, the cast, and production designer Amanda Stekly, we ended up moving the bed so that the camera could shoot the actors from behind, looking towards the window. This of course made for much more interesting and dimensional lighting.
The window looked out onto the street, and with a narrow pavement and no permission from the council, rigging a light outside was out of the question. Furthermore, we knew that the sun was going to shine right into that window later in the day, seriously messing with our continuity. Unfortunately all we could do was ask Amanda to dress in a net curtain. This took the worst of the harshness out of any direct sun and hopefully disguised the natural changes in light throughout the day at least a little.
When the sun did blast in through the window at about 6pm, we added a layer of unbleached muslin behind the net curtain to soften it further. We doubled this as the angle of the sun got more straight-on, then removed it entirely when the sun vanished behind the rooftops opposite at 7pm. About 20 minutes later we rigged a daylight LED panel in the room, bouncing off the ceiling, as a fill to counteract the diminishing natural light. We wrapped just as it was becoming impossible to match to earlier takes.
We were shooting in RAW on a Canon C200, which should give some grading latitude to help match takes from different times of day. The split-screen nature of the film means that the match needs to be very close though!
As I write this, the film is still in postproduction, and I very much look forward to seeing how it comes out. I’ll leave you with the start and end frames from slate 2, take 17, with a very quick and dirty grade.
Where do you start, as a director of photography lighting a set? What should be the first brushstroke when you’re painting with light?
I believe the answer is backlight, and I think many DPs would agree with me.
Let’s take the example of a night exterior in a historical fantasy piece, as featured in my online course, Cinematic Lighting. The main source of light in such a scene would be the moon. Where am I going to put it? At the back.
The before image is lit by an LED panel serving purely as a work-light while we rehearsed. It’s not directly above the camera, but off to the right, so the lighting isn’t completely flat, but there is very little depth in the image. Beyond the gate is a boring black void.
The after image completely transforms the viewer’s understanding of the three-dimensional space. We get the sense of a world beyond the gate, an intriguing world lighter than the foreground, with a glimpse of trees and space. Composing the brazier in the foreground has added a further plane, again increasing the three-dimensional impression.
Here is the lighting diagram for the scene. (Loads more diagrams like this can be seen on my Instagram feed.)
The “moon” is a 2.5KW HMI fresnel way back amongst the trees, hidden from camera by the wall on the right. This throws the gate and the characters into silhouette, creating a rim of light around their camera-right sides.
To shed a little light on Ivan’s face as he looks camera-left, I hid a 4×4′ Kino Flo behind the lefthand wall, again behind the actors.
The LED from the rehearsal, a Neewer 480, hasn’t moved, but now it has an orange gel and is dimmed very low to subtly enhance the firelight. Note how the contrasting colours in the frame add to the depth as well.
So I’ll always go into a scene looking at where to put a big backlight, and then seeing if I need any additional sources. Sometimes I don’t, like in this scene from the Daylight Interior module of the course.
Backlight for interior scenes is different to night interiors. You cannot simply put it where you want it. You must work with the position of the windows. When I’m prepping interiors, I always work with the director to try to block the scene so that we can face towards the window as much as possible, making it our backlight. If a set is being built, I’ll talk to the production designer at the design stage to get windows put in to backlight the main camera positions whenever possible.
In the above example, lit by just the 2.5K HMI outside the window, I actually blacked out windows behind camera so that they would not fill in the nice shadows created by the backlight.
Daylight exteriors are different again. I never use artificial lights outdoors in daytime any more. I prefer to work with the natural light and employ reflectors, diffusion or negative fill to mould it where necessary.
So it’s very important to block the scene with the camera facing the sun whenever possible. Predicting the sun path may take a little work, but it will always be worth it.
Here I’ve shot south, towards the low November sun, and didn’t need to modify the light at all.
Shooting in the opposite direction would have looked flat and uninteresting, not to mention causing potential problems with the cast squinting in the sunlight, and boom and camera shadows being cast on them.
You can learn much more about the principles and practice of cinematic lighting by taking my online course on Udemy. Currently you can get an amazing 90% off using the voucher code INSTA90 until November 19th.
Last week, Greig Fraser, ASC, ACS and Baz Idoine were awarded the Emmy for Outstanding Cinematography for a Single-camera Series (Half-hour) for The Mandalorian. I haven’t yet seen this Star Wars TV series, but I’ve heard and read plenty about it, and to call it a revolution in filmmaking is not hyperbole.
Half of the series was not shot on location or on sets, but on something called a volume: a stage with walls and ceiling made of LED screens, 20ft tall, 75ft across and encompassing 270° of the space. I’ve written before about using large video screens to provide backgrounds in limited aways, outside of train windows for example, and using them as sources of interactive light, but the volume takes things to a whole new level.
In the past, the drawback of the technology has been one of perspective; it’s a flat, two-dimensional screen. Any camera movement revealed this immediately, because of the lack of parallax. So these screens tended to be kept to the deep background, with limited camera movement, or with plenty of real people and objects in the foreground to draw the eye. The footage shown on the screens was pre-filmed or pre-rendered, just video files being played back.
The Mandalorian‘s system, run by multiple computers simultaneously, is much cleverer. Rather than a video clip, everything is rendered in real time from a pre-built 3D environment known as a load, running on software developed for the gaming industry called Unreal Engine. Around the stage are a number of witness cameras which use infra-red to monitor the movements of the cinema camera in the same way that an actor is performance-captured for a film like Avatar. The data is fed into Unreal Engine, which generates the correct shifts in perspective and sends them to the video walls in real time. The result is that the flat screen appears, from the cinema camera’s point of view, to have all the depth and distance required for the scene.
The loads are created by CG arists working to the production designer’s instructions, and textured with photographs taken at real locations around the world. In at least one case, a miniature set was built by the art department and then digitised. The scene is lit with virtual lights by the DP – all this still during preproduction.
The volume’s 270° of screens, plus two supplementary, moveable screens in the 90° gap behind camera, are big enough and bright enough that they provide most or all of the illumination required to film under. The advantages are obvious. “We can create a perfect environment where you have two minutes to sunset frozen in time for an entire ten-hour day,” Idoine explains. “If we need to do a turnaround, we merely rotate the sky and background, and we’re ready to shoot!”
Traditional lighting fixtures are used minimally on the volume, usually for hard light, which the omni-directional pixels of an LED screen can never reproduce. If the DPs require soft sources beyond what is built into the load, the technicians can turn any off-camera part of the video screens into an area of whatever colour and brightness are required – a virtual white poly-board or black solid, for example.
A key reason for choosing the volume technology was the reflective nature of the eponymous Mandalorian’s armour. Had the series been shot on a green-screen, reflections in his shiny helmet would have been a nightmare for the compositing team. The volume is also much more actor- and filmmaker-friendly; it’s better for everyone when you can capture things in-camera, rather than trying to imagine what they will look like after postproduction. “It gives the control of cinematography back to the cinematographer,” Idoine remarks. VR headsets mean that he and the director can even do a virtual recce.
The Mandalorian shoots on the Arri Alexa LF (large format), giving a shallow depth of field which helps to avoid moiré problems with the video wall. To ensure accurate chromatic reproduction, the wall was calibrated to the Alexa LF’s colour filter array.
Although the whole system was expensive to set up, once up and running it’s easy to imagine how quickly and cheaply the filmmakers can shoot on any given “set”. The volume has limitations, of course. If the cast need to get within a few feet of a wall, for example, or walk through a door, then that set-piece has to be real. If a scene calls for a lot of direct sunlight, then the crew move outside to the studio backlot. But undoubtedly this technology will improve rapidly, so that it won’t be long before we see films and TV episodes shot entirely on volumes. Perhaps one day it could overtake traditional production methods?
A simple enough slug line, and fairly common, but amongst the most challenging for a cinematographer. In this article I’ll break down into five manageable steps my process of lighting woodlands at night.
1. Set up the moon.
Forests typically have no artificial illumination, except perhaps practical torches carried by the cast. This means that the DP will primarily be simulating moonlight.
Your “moon” should usually be the largest HMI that your production can afford, as high up and far away as you can get it. (If your production can’t afford an HMI, I would advise against attempting night exteriors in a forest.) Ideally this would be a 12K or 18K on a cherry-picker, but in low-budget land you’re more likely to be dealing with a 2.5K on a triple wind-up stand.
Why is height important? Firstly, it’s more realistic. Real moonlight rarely comes from 15ft off the ground! Secondly, it’s hard to keep the lamp out of shot when you’re shooting towards it. A stand might seem quite tall when you’re right next to it, but as soon as you put it far away, it comes into shot quite easily. If you can use the terrain to give your HMI extra height, or acquire scaffolding or some other means of safely raising your light up, you’ll save yourself a lot of headaches.
The size of the HMI is of course going to determine how large an area you can light to a sufficient exposure to record a noise-free image. Using a good low-light camera is going to help you out here. I shot a couple of recent forest night scenes on a Blackmagic Pocket Cinema Camera, which has dual native ISOs, the higher being 3200. Combined with a Speedbooster, this camera required only 1 or 2 foot-candles of illuminance, meaning that our 2.5K HMI could be a good 150 feet away from the action. (See also: “How Big a Light do I Need?”)
2. Plan for the reverse.
A fake moon looks great as a backlight, but what happens when it comes time to shoot the reverse? Often the schedule is too tight to move the HMI all the way around to the other side, particularly if it’s rigged up high, so you may need to embrace it as frontlight.
Frontlight is generally flat and undesirable, but it can be interesting when it’s broken up with shadows, and that’s exactly what the trees of a forest will do. Sometimes the pattern of light and dark is so strong and camouflaging that it can be hard to pick out your subject until they move. One day I intend to try this effect in a horror film as a way of concealing a monster.
One thing to look out for with frontlight is unwanted shadows, i.e. those of the camera and boom. Again, the higher up your HMI is, the less of an issue this will be.
If you can afford it, a second HMI set up in the opposite direction is an ideal way to maintain backlight; just pan one off and strike up the other. I’ve known directors to complain that this breaks continuity, but arguably it does the opposite. Frontlight and backlight look very different, especially when smoke is involved (and I’ll come to that in a minute). Isn’t it smoother to intercut two backlit shots than a backlit one and frontlit one? Ultimately it’s a matter of opinion.
3. Consider Ground lights.
One thing I’ve been experimenting with lately is ground lights. For this you need a forest that has at least a little undulation in its terrain. You set up lights directly on the ground, pointed towards camera but hidden from it behind mounds or ridges in the deep background.
I once tried this with an HMI and it just looked weird, like there was a rave going on in the next field, but with soft lights it is much more effective. Try fluorescent tubes, long LED panels or even rows of festoon lights. When smoke catches them they create a beautiful glow in the background. Use a warm colour to suggest urban lighting in the distance, or leave it cold and it will pass unquestioned as ambience.
Put your cast in front of this ground glow and you will get some lovely silhouettes. Very effective silhouettes can also be captured in front of smoky shafts of hard light from your “moon”.
4. Fill in the faces.
All of the above looks great, but sooner or later the director is going to want to see the actors’ faces. Such is the cross a DP must bear.
On one recent project I relied on practical torches – sometimes bounced back to the cast with silver reflectors – or a soft LED ball on a boom pole, following the cast around.
Big-budget movies often rig some kind of soft toplight over the entire area they’re shooting in, but this requires a lot of prep time and money, and I expect it’s quite vulnerable to wind.
A recipe that I use a lot for all kinds of night exteriors is a hard backlight and a soft sidelight, both from the same side of camera. You don’t question where the sidelight is coming from when it’s from the same general direction as the “moon” backlight. In a forest you just have to be careful not to end up with very hot, bright trees near the sidelight, so have flags and nets at the ready.
5. Don’t forget the Smoke.
Finally, as I’ve already hinted, smoke is very important for a cinematic forest scene. The best options are a gas-powered smoke gun called an Artem or a “Tube of Death”. This latter is a plastic tube connected to a fan and an electric smoke machine. The fan forces smoke into the tube and out of little holes along its length, creating an even spread of smoke.
All smoke is highly suspectible to changes in the wind. An Artem is easier to pick up and move around when the wind changes, and it doesn’t require a power supply, but you will lose time waiting for it to heat up and for the smoke and gas canisters to be changed. Whichever one you pick though, the smoke will add a tremendous amount of depth and texture to the image.
Overall, nighttime forest work scenes may be challenging, but they offer some of the greatest opportunities for moody and creative lighting. Just don’t forget your thermals and your waterproofs!
Good lighting can boost the production values of a film tremendously, making the difference between an amateur and a professional-looking piece. For filmmakers early in their careers, however, the equipment typically used to achieve these results can be prohibitively expensive. Far from the Hollywood productions attended by trucks full of lights, a micro-budget film may be unable to rent even a single HMI. Do not despair though, as there are ways to light scenes well without breaking the bank. Here are my top six tips for lighting on the cheap.
1. Make the most of natural light
The hardest shots to light without the proper equipment are wide shots. Where a fully-budgeted production would rig Maxi Brutes on cherry-pickers, or pound HMIs through windows, a filmmaker of limited means simply won’t have access to the raw power of such fixtures. Instead, plan your day carefully to capture the wide shots at the time when natural light gives you the most assistance. For a day interior, this means shooting when the sun is on the correct side of the building.
There are a plethora of LED fixtures on the market, designed for all kinds of applications, some of them very reasonably priced. It might be tempting to purchase some of these to provide your primary illumination, but I advise against it. Cheap LED units (and fluorescents) have a terrible Colour Rendering Index (CRI), making for unnatural and unappealing skintones. Such units are therefore best restricted to backgrounds, accent lighting and “specials”. For example, I purchased a little LED camping light from a charity shop for about £2, and I often use it to create the blue glow from computer screens or hang it from the ceiling to produce a hint of hair-light.
By far the best solution for a high output, high CRI, low cost key is a halogen floodlight; 500W models are available for as little as £5. Their chief disadvantage is the lack of barn doors, making the light hard to control, though if you can stretch to a roll of black wrap you can fashion a kind of snoot. Alternatively, consider investing in a secondhand tungsten movie fixture. With many people switching to LEDs, there are plenty of old tungsten units out there. Try to get a reputable brand like Arri or Ianiro, as some of the unbranded units available on Ebay are poorly wired and can be unsafe.
Flooding a halogen light onto a scene is never going to look good, but then the same is often true of dedicated movie fixtures. Instead it’s more how you modify the light that creates the nuanced, professional look. Improvise flags from pieces of cardboard to stop the light spilling into unwanted places – but be VERY careful how close you put them to a tungsten or halogen source, as these get extremely hot. For example, when shooting indoors, flag light off the background wall (especially if it’s white or cream) to help your subject stand out.
Almost all cinematographers today prefer the subtlety of soft light to the harshness of hard light. You can achieve this by bouncing your fixture off a wall or ceiling, or a sheet of polystyrene or card. Or you could hang a white bedsheet or a shower curtain in front of the light as diffusion, but again be sure to leave a safe distance between them. Professional collapsible reflectors are available very cheaply online, and can be used in multiple ways to diffuse or reflect light.
Finally, don’t be afraid to use existing practical lighting in your scene. Turning on the main overhead light usually kills the mood, but sometimes it can be useful. You can generate more contrast and shape by covering up the top of the lampshade, thus preventing ceiling bounce, or conversely use the ceiling bounce to give some ambient top-light and cover the bottom of the lampshade to prevent a harsh hotspot underneath it. Table lamps and under-cupboard kitchen lights can add a lot of interest and production value to your backgrounds. If possible, swap out LED or fluorescent bulbs for conventional tungsten ones for a more attractive colour and to eliminate potential flickering on camera.
Many light sources we come across today have a CRI rating. Most of us realise that the higher the number, the better the quality of light, but is it really that simple? What exactly is Colour Rendering Index, how is it measured and can we trust it as cinematographers? Let’s find out.
What is C.R.I.?
CRI was created in 1965 by the CIE – Commission Internationale de l’Eclairage – the same body responsible for the colour-space diagram we met in my post about How Colour Works. The CIE wanted to define a standard method of measuring and rating the colour-rendering properties of light sources, particularly those which don’t emit a full spectrum of light, like fluorescent tubes which were becoming popular in the sixties. The aim was to meet the needs of architects deciding what kind of lighting to install in factories, supermarkets and the like, with little or no thought given to cinematography.
As we saw in How Colour Works, colour is caused by the absorption of certain wavelengths of light by a surface, and the reflection of others. For this to work properly, the light shining on the surface in the first place needs to consist of all the visible wavelengths. The graphs below show that daylight indeed consists of a full spectrum, as does incandescent lighting (e.g. tungsten), although its skew to the red end means that white-balancing is necessary to restore the correct proportions of colours to a photographed image. (See my article on Understanding Colour Temperature.)
Fluorescent and LED sources, however, have huge peaks and troughs in their spectral output, with some wavelengths missing completely. If the wavelengths aren’t there to begin with, they can’t reflect off the subject, so the colour of the subject will look wrong.
Analysing the spectrum of a light source to produce graphs like this required expensive equipment, so the CIE devised a simpler method of determining CRI, based on how the source reflected off a set of eight colour patches. These patches were murky pastel shades taken from the Munsell colour wheel (see my Colour Schemes post for more on colour wheels). In 2004, six more-saturated patches were added.
The maths which is used to arrive at a CRI value goes right over my head, but the testing process boils down to this:
Illuminate a patch with daylight (if the source being tested has a correlated colour temperature of 5,000K or above) or incandescent light (if below 5,000K).
Compare the colour of the patch to a colour-space CIE diagram and note the coordinates of the corresponding colour on the diagram.
Now illuminate the patch with the source being tested.
Compare the new colour of the patch to the CIE diagram and note the coordinates of the corresponding colour.
Calculate the distance between the two sets of coordinates, i.e. the difference in colour under the two light sources.
Repeat with the remaining patches and calculate the average difference.
Here are a few CRI ratings gleaned from around the web:
LitePanels 1×1 LED
Problems with C.R.I.
There have been many criticisms of the CRI system. One is that the use of mean averaging results in a lamp with mediocre performance across all the patches scoring the same CRI as a lamp that does terrible rendering of one colour but good rendering of all the others.
Further criticisms relate to the colour patches themselves. The eight standard patches are low in saturation, making them easier to render accurately than bright colours. An unscrupulous manufacturer could design their lamp to render the test colours well without worrying about the rest of the spectrum.
In practice this all means that CRI ratings sometimes don’t correspond to the evidence of your own eyes. For example, I’d wager that an HMI with a quoted CRI in the low nineties is going to render more natural skin-tones than an LED panel with the same rating.
I prefer to assess the quality of a light source by eye rather than relying on any quoted CRI value. Holding my hand up in front of an LED fixture, I can quickly tell whether the skin tones looks right or not. Unfortunately even this system is flawed.
The fundamental issue is the trichromatic nature of our eyes and of cameras: both work out what colour things are based on sensory input of only red, green and blue. As an analogy, imagine a wall with a number of cracks in it. Imagine that you can only inspect it through an opaque barrier with three slits in it. Through those three slits, the wall may look completely unblemished. The cracks are there, but since they’re not aligned with the slits, you’re not aware of them. And the “slits” of the human eye are not in the same place as the slits of a camera’s sensor, i.e. the respective sensitivities of our long, medium and short cones do not quite match the red, green and blue dyes in the Bayer filters of cameras. Under continuous-spectrum lighting (“smooth wall”) this doesn’t matter, but with non-continuous-spectrum sources (“cracked wall”) it can lead to something looking right to the eye but not on camera, or vice-versa.
Given its age and its intended use, it’s not surprising that CRI is a pretty poor indicator of light quality for a modern DP or gaffer. Various alternative systems exist, including GAI (Gamut Area Index) and TLCI (Television Lighting Consistency Index), the latter similar to CRI but introducing a camera into the process rather than relying solely on human observation. The Academy of Motion Picture Arts and Sciences recently invented a system, Spectral Similarity Index (SSI), which involves measuring the source itself with a spectrometer, rather than reflected light. At the time of writing, however, we are still stuck with CRI as the dominant quantitative measure.
So what is the solution? Test, test, test. Take your chosen camera and lens system and shoot some footage with the fixtures in question. For the moment at least, that is the only way to really know what kind of light you’re getting.
The publicity machine is ramping up for Kenneth Branagh’s Murder on the Orient Express remake, and it’s got me thinking about the challenges of a script set largely on a moving train. There are a number of ways of realising such scenes, and today I’m going to look at five movies that demonstrate different techniques. All of these methods are equally applicable to scenes in cars or any other moving vehicle.
1. For Real: “The Darjeeling limited”
Wes Anderson’s 2007 film The Darjeeling Limited sees three brothers embarking on a spiritual railway journey across India. Many of the usual Anderson tropes are present and correct – linear tracking shots, comical headgear, Jason Schwartzman – but surprisingly the moving train wasn’t done with some kind of cutesy stop-motion. Production designer Mark Friedberg explains:
The big creative decision Wes made was that we were going to shoot this movie on a moving train. And all that does is complicate life. It makes it more expensive, it makes the logistics impossible. It made it incredibly difficult to figure out how many crew, what crew, what gear… but what it did do is it made it real.
Kenneth Branagh has stated that at least some of Murder on the Orient Express was shot on a real moving train too:
They painstakingly built a fully functioning period authentic locomotive and carriages from the Orient Express during the golden, glamorous age of travel. It was a train that moved… All of our actors were passengers on the train down the leafy lanes of Surrey, pretending to be the former Yugoslavia.
2. Poor Man’s Process: “The Double”
Although best known as The IT Crowd‘s Moss and the new host of the Crystal Maze, Richard Ayoade is also an accomplished director. His last feature was a darkly beautiful adaptation of Dostoyevsky’s classic identity-crisis novella The Double.
Unlike the other movies on this list, The Double only has short sequences on a train, and that’s a key point. So named because it’s a cheap alternative to rear projection (a.k.a. process photography), Poor Man’s Process is a big cheat. In order to hide the lack of motion, you keep the view outside your vehicle’s windows blank and featureless – typically a night sky, but a black subway tunnel or a grey daytime sky can also work. Then you create the illusion of motion with dynamic lighting, a shaky camera, and grips rocking the carriage on its suspension. Used judiciously, this technique can be very convincing, but you would never get away with it for a whole movie.
Poor Man’s works particularly well in The Double, the black void outside the subway car playing into the oppressive and nightmarish tone of the whole film. In an interview with Pushing Pixels, production designer David Crank explains how the subway carriage set was built out of an old bus. He goes on to describe how the appearance of movement was created:
We put the forks of a forklift under the front of the bus, and shook it… For the effect of moving lights outside the train, it was a combination of some spinning lights on stands, as well as lights on small rolling platforms which tracked back and forth down the outside of the bus.
Duncan “Zowie Bowie” Jones followed up his low-budget masterpiece Moon with Hollywood sci-fi thriller Source Code, a sort of mash-up of Quantum Leap and Groundhog Day with a chilling twist. It takes place predominantly on a Chicago-bound commuter train, in reality a set surrounded by green screen. In the featurette above, Jones mentions that shooting on a real moving train was considered, but ultimately rejected in favour of the flexibility of working on stage:
Because we revisit an event multiple times, it was absolutely integral to making it work, and for the audience not to get bored, that we were able to vary the visuals. And in order to do that we had to be able to build platforms outside of the train and be able to really vary the camera angles.
In the DVD commentary, Jones also notes that the background plates were shot in post from a real train “loaded up with cameras”.
It’s difficult to make it feel like natural light is coming in and still get the sense of movement on a train… We worked with computer programs where we actually move the light itself, and brighten and dim the lights so it feels as if you are travelling… The lights are never 100% constant.
When I shot The Little Mermaid last year we did some train material against green screen. To make the lighting dynamic, the grips built “branch-a-loris” rigs: windmills of tree branches which they would spin in front of the lamps to create passing shadows.
4. Rear projection: “Last Passenger”
Perhaps the most low-budget film on this list, Last Passenger is a 2013 independent thriller set aboard a runaway train. Director Omid Nooshin and DP Angus Hudson wanted a vintage look, choosing Cooke Xtal anamorphic lenses and a visual effects technique that had long since fallen out of favour: rear projection.
Before the advent of optical – and later digital – compositing, rear projection was commonly used to provide moving backgrounds for scenes in vehicles. The principle is simple: the pre-recorded backgrounds are projected onto a screen like this…
Hudson goes into further detail on the technique as used for the Last Passenger:
To capture [the backgrounds] within our limited means, we ended up shooting from a real train using six Canon 5D cameras, rigged in such a way that we got forward, sideways and rear-facing views out of the train at the same time. We captured a huge amount of footage, hours and hours of footage. That allowed us to essentially have 270 degrees of travelling shots, all of which were interlinked.
Because rear projection is an in-camera technique, Nooshin and Hudson were able to have dirt and water droplets on the windows without worrying about creating a compositing nightmare in postproduction. Hudson also notes that the cast loved being able to see the backgrounds and react to them in real time.
5. L.E.D. Panels: “Train to Busan”
Enabling the actors to see the background plates was also a concern for Yeon Sang-ho, director of the hit Korean zombie movie Train to Busan. He felt that green screen would make it “difficult to portray the reality”, so he turned to the latest technology: LED screens. This must have made life easier not just for the cast, but for the cinematographer as well.
You see, when you travel by train in the daytime, most of the light inside the carriage comes from outside. Some of it is toplight from the big, flat sky, and some of it is hard light from the sun – both of these can be faked, as we’ve seen – but a lot of the light is reflected, bouncing off trees, houses, fields and all the other things that are zipping by. This is very difficult to simulate with traditional means, but with big, bright LED screens you get this interactive lighting for free. Because of this, and the lack of postproduction work required, this technique is becoming very popular for car and train scenes throughout the film and TV industry.
This brings us back to Murder on the Orient Express, for which 2,000 LED screens were reportedly employed. In a Digital Spy article, Branagh notes that this simulated motion had an unintended side effect:
It was curious that on the first day we used our gimballed train sets and our LED screens with footage that we’d gone to great trouble to shoot for the various environments – the lowlands and then the Alps, etc… people really did feel quite sick.
I’ll leave you with one final point of interest: some of the above films designed custom camera tracks into their train carriage sets. On Last Passenger, for example, the camera hung from a dolly which straddled the overhead luggage racks, while The Darjeeling Limited had an I-beam track designed into the centre of the ceiling. Non-train movies like Speed have used the same technique to capture dolly shots in the confines of a moving vehicle.
From time to time I help out my friend Kate Madison shooting show reels for actors. The fun and the challenge is in creating and lighting little micro-sets to capture angles that look like they might be lifted out of a scene from a much larger production, all with limited equipment.
Here’s an interesting shot from a recent showreel for Dana Hajaj. This was intended to resemble a Good Wife style legal drama, though actually the first reference that the lawyer’s office setting brought to my mind was Ally McBeal. I remember how they often had hot sunlight coming in through their office windows which would hit the talent from the chest down, while softer, indirect daylight would illuminate the faces.
Clearly this technique wasn’t exactly going to work for an MCU, but it did get me thinking about windows as two-in-one sources: a hard source which adds interest and ‘sheen’ to the image but is too harsh to hit faces with, and a soft sources for faces. Often cinematographers will use two different lights through the same window to achieve these two distinct effects. (I sometimes employ what I call a “Window Wrap” to this end.)
Now, the set for this showreel shot was just a red wall and sconce. (We tried a plant in the corner but couldn’t get it to work.) I wanted to suggest what the rest of the set might be, beyond the borders of this MCU, and simulating a window seemed like a natural choice. Furthermore, a window with Venetian blinds would help sell what was really a living room as a place of business. But this was not film noir; I didn’t want stripes of light on Dana’s face. Instead I used them to add interest to the wall.
Kate had a slatted-top stool in the hall which threw convincing “blinds” shadows when clamped to a C-stand in front of an 800W Arrilite. Ideally the shadows would have been sharper, but without a Dedo or a par this was the best I could do.
To get the maximum richness from the practical, I put a topper (black wrap clipped to the stool!) on the 800 to keep it off the sconce, and placed CTO inside the lampshade to warm up the fluorescent bulb.
To key Dana, I fired a 1K Arrilite into a 4’x4′ polyboard which was positioned next to the stool. Tungsten bounced off poly gives a beautiful soft, matt quality of light, and is a great way to key talent.
The backlight comes from a 1’x1′ LED panel set to about 4500K. What is the motivation for this source? North light coming from another window maybe? The great thing about micro-sets is there’s no wide shot so I don’t have to worry about that if I don’t want to! The motivation is that cold backlight looks good on black hair, and that’s that.
As we prepared to roll, I wondered if I should increase the contrast more. I could have done this by (a) flagging the poly bounce to prevent it filling in the “blinds” shadows on the wall and (b) bringing in negative fill on the talent’s camera right side to kill the ambience. But I decided that more contrast was not appropriate for this kind of piece.
For another scene for Dana’s reel, we mocked up a remote Arabian campsite on Kate’s patio! Kate used a piece of fabric hung from a post and two light stands to represent the tent.
I wanted to give the impression that if we cut to a wide shot – which of course we never do, but if we did – that it would show a vast landscape, perhaps a desert, all backlit by moonlight. On this hypothetical production, I would generate that moonlight with 18Ks on condor cranes, gelled with Steel Blue.
But on this tight shot I was able to achieve the same effect with two far smaller sources, both gelled with Steel Blue. (This is a blue with more green in it than CTB. It’s prettier and has connotations of many 80s and 90s thrillers and action movies that seemed to use copious amounts of this gel.) In the deep background is an LED panel, 3/4 backlighting a couple of blurry apple trees that could maybe play as vegetation around an oasis. Immediately behind the “tent” is a 40″ C-stand, top floor, with a 1K Arrilite on it. So close to the talent, the 1K comes down at a steep enough angle to imply moonlight, or an 18K on a condor, depending on how you want to look at it.
The flames from the fire pit weren’t doing much to light Dana, so I bounced another 1K off a gold reflector on the floor next to the fire. During takes I wiggled the reflector to add dynamics to the light.
To add a final touch of production value, I suggested a foreground practical. Kate found a candle lantern which we hung from a flag arm just in front of camera. Every frame of a Blockbuster movie is packed with details, so things like this help a lot to sell the scale.