Lighting for Film: The Complete Beginner's Guide

Hi, my name is Luc Ong and I work as a cinematographer. I've been wanting to put together this course in order to share with you all what I consider to be the most important lessons I learned about cinematic lighting throughout my formative years in film school. The idea came to me in 2020 when all work came to a halt and several of my fellow filmmakers asked me for a crash course in lighting. I believe this class would benefit any up-and-coming cinematographers, gaffers, key grips, but also directors who'd like to communicate more precisely with their DPs. I owe all of this knowledge to professors John Crawford and Gordon Arkenberg, two absolutely fantastic teachers at New York University whose heart for teaching are pure and beautiful. Let's begin. So how can we understand and work with light which can seem so abstract and intangible? One way to think of lighting is to think of it as having five distinct characteristics or attributes. Namely, direction, quality, also known as softness, color, intensity, and cut and shape. We'll also see why it is important to think of these attributes in this specific order when working on set. So the first characteristic we have is lighting direction. It is probably the most important characteristic because of how heavily it dictates the mood of a scene. The light direction is also what takes longest to adjust on set, so it is important to get it right first. We will look at different lighting directions with a diagram that illustrates where the light is placed relative to the subject, footage of how it appears on camera, and behind-the-scenes footage showing where those lights were placed to get the result. Most importantly, I'd like to invite you to ask yourself, how do these different lighting placements make me feel as an audience? And do they already, in and of themselves, tell a specific story? So let's begin with a front light. Front lighting is achieved by placing the light on axis with the camera. It can be done with the unit placed behind the camera, or in front of it, and above the frame. Rarely do we see this lighting direction because it can easily make your image look flat or two-dimensional. As cinematographers, we're trying to reproduce a three-dimensional world on a two-dimensional medium. To do so, we have to use what painters call chiaroscuro, namely, alternations between areas of light and shadows, or simply put, contrast. So why is it difficult to achieve contrast with a front light? Well, there are two main reasons. One is that you'd most likely illuminate all the shadows on your subject's face, which will decrease the perception of depth on their faces. And two, because by front lighting, you'd also most likely illuminate the background right behind your subject, making it difficult for you to make the background darker without affecting the light falling on your subject. And you usually want the background to be somewhat darker than your subject in order to, once again, create contrast between the foreground and background elements of your image, and thus making your subject pop out. More on that later. One way to still be able to make your background darker with a front light is to make sure that your light is high enough to be able to use what people call a topper, which is a flag or a net that cuts off the top portion of the light beam which would hit your background without affecting the light falling on your subject. Next, we have what's commonly known as a butterfly light. This placement allows you to front light your subject while retaining some contrast on your subject's face, as well as some contrast between your subject and your background. To achieve a butterfly light, you'd want to place the light in front of your subject and high enough, pointed down, to create this butterfly-shaped nose shadow. You'll notice that the cheekbones also create their own shadows, which creates more depth in your subject's face. It is much easier to control the light falling on the background with a butterfly light as the light is pointing down at your subject. You can then use a barn door, a topper, or a skirt to cut off the light spilling on the background. It is important to note that a butterfly light doesn't look appealing on all faces. Deep eye sockets, for example, can be a challenge with this type of lighting, but a bounce board placed under your talent to fill in the shadows would usually help with that. Next, we have what's commonly called a Rembrandt light. Named after the Dutch painter who used this technique in several of his pieces, it is easily recognizable by the way the nose shadow creates a triangle of light on the shadow side of your talent's face. It is a wonderful way to light both sides of a face with one light as it looks really natural, pleasing, and three-dimensional. Because of this, it is very commonly used in movies and can be found almost everywhere. To achieve this look, you'd want to position your light roughly 45° off-axis to your subject's eyeline and have the light pointed down at about a 45° angle. This will allow the light to reach both sides of the face, creating this pleasant nose shadow. That kind of blends in with the smile line of the face. Next, we have the side light. In this scenario, the light is placed at about 90° off-axis relative to your subject's eyeline, creating a very dramatic look where half of the face is lit while the other half is in shadows. In most cases, you'd want to place the light slightly closer on-axis with the camera in order to avoid this shadow cast by the talent's cheek itself. So instead of it being a complete 90° angle, you're looking more at a 80° angle. Next, we have what's commonly called a kicker, or an edge light. For this setup, we'd want our light to be placed anywhere between 15 to 45° behind your subject, creating this highlight around the shoulders that can wrap around the cheek however much you'd like depending on how far off-axis the light is. It can be used on its own, as in this example, but will most likely be paired with a reflector in front of your subject to balance out the contrast, or in addition to a key light. It's a wonderful way to create more depth to your image as it creates yet another layer of alternation between light and shadow and helps separate your subject from the background as you can see in this example. And finally, we have the backlight. A backlight can be recognized by the highlight it creates around the subject's shoulders and it is achieved by placing the light directly behind your subject. The main difference between a backlight and a kicker is that the backlight doesn't wrap around the subject's cheek. Just like a kicker, it can be used on its own or to complement your key light to create more separation between your subject and the background. Unless you're purposely trying to flare your lens, you usually have your backlight high enough and pointed down to avoid any unwanted flare or glare on the lens. Generally speaking, no matter what lighting direction you choose to use, you'd often have the light high up and pointed down at your subject so that their shadow falls on the ground in a natural way, helping you avoid seeing the shadows on the walls. But there's really no rule here. Sometimes you do want to see the shadow to evoke a certain emotion. A great way to study lighting while watching movies is to ask yourself the following questions. Where is the light coming from? And how does it make me feel? The answer to the latter is quite personal and will differ from person to person. The former can easily be answered by looking at where the shadow created by the nose is falling. If there's no nose shadow and the face is lit up evenly, then it's a front light. If there's a butterfly-shaped shadow under the nose, then it's a butterfly light. If the nose shadow forms a triangle of light on the shadow side, then it's a Rembrandt light. If the nose shadow is invisible because the face is split in half between light and shadow, then it's a side light. Also keep in mind that lighting is dynamic. A single light can hit your talents in different ways depending on where they are, which is why it is so important as cinematographers to collaborate with the director when it comes to blocking. For example, in this scene from La Haine, directed by Mathieu Kassovitz and shot by Pierre Haim, this one key light acts as a backlight on Vince, a Rembrandt light on Hubert, and a very toppy butterfly light on Saïd. Additionally, I find it helpful to think of cinematography as an interpretation of reality rather than a scientific recreation of it. For example, in this scene from Lord of the Rings, The Two Towers, you will notice that while the two characters are facing each other, they're both getting backlit by the sun. It doesn't make sense logically, but it does make sense emotionally, as having the light fall on them in a similar fashion creates cohesion to both images and put these two characters on the same emotional plane. In this other example, the key light changes direction completely when we cut from the wide shot to the close-up. In this other example, the actor is supposed to be lit by the candles under her, but the cinematographer used a supplemental light placed in a Rembrandt position instead. Generally speaking, you can get away with the light coming from an unrealistic direction as long as the other characteristics of light somewhat follow what you'd expect the light to look like in real life, which brings us to our next lighting characteristic, quality, also known as softness. The softness of a light refers to how defined or undefined the shadow created by the subject appears when hit by the light. A hard light refers to a light that would create shadows which edges are well-defined, while a soft light refers to a light that creates shadow edges that aren't well-defined. So, what makes a light hard or soft? The quality or softness of the light is determined by the size of the light source relative to the size of the subject. The bigger the light source is relative to your subject's size, the softer the light will appear. Alternatively, the smaller the light source is relative to your subject's size, and the harder the light will appear. It is important to understand that it is the relative size between your light source and your subject that determines the softness of the light. This means that a large source can still create hard shadows if it is placed far away from your subject, as it would appear relatively small from your subject's perspective. The sun is a perfect example of that. Likewise, a small light source can also appear soft if you're lighting a very small subject. Understanding that, it is easy to understand why diffusing a light makes it softer. Whether it be with a diffusion sheet attached to the barn door or with a diffusion frame, all we're doing is making the light source bigger in relation to our subject. From your subject's point of view, you're going from a light this big to a light that big. This idea of a larger light source creating softer shadows is easily understood when looking at this diagram from the ASC article called Diffusion Confusion, which I'd highly recommend anyone reading if you feel called to explore this concept further. This paragraph from the article summarizes it perfectly. A shadow isn't just a shadow, it's actually made up of two components, the umbra, which is the zone labeled as U on the diagram, and the penumbra, the zone labeled as P. The umbra of a shadow is the deep, dark center of it. If your light source is a point source from a distance, and there's nothing nearby to scatter and fill in that light, then your shadow will be pure umbra, sharp and well-defined. The penumbra is the secondary portion of the shadow, the fuzzy perimeter created by oblique rays of light coming around the edges of the subject. Hard light has a very small penumbra, or none at all. Soft light has a very large penumbra, with little or no umbra. So understanding this, how can we creatively manipulate the softness of our light on set? You can do so in many ways. For example, you can diffuse the light source to make it bigger and thus softer, but you can also move that soft light closer to your subject to make it even softer, as its relative size to your subject would then increase. The opposite is true where you can move your light away from your subject to make it harder. If you want the softest light out of a diffusion frame, make sure to fill the frame as evenly as possible to once again make the light source, which is now the diffusion frame by the way, bigger. If the diffused light appears too soft and you don't have the room or the time to back up the light, you can spot the unit to make it harder. Generally speaking, a soft light would soften things like pimples, pores and wrinkles, because the bigger light will fill in the shadows created by the natural textures of the skin. And it is helpful to know that if you're trying to extend a light, meaning to add your own film light, while pretending that this light is still coming from a source that is visible in frame, such as a window or a practical lamp, that you can more easily get away with making the added film light softer than what the actual source would be in real life, rather than making it harder. Again, we're not trying to scientifically recreate this reality, but rather to interpret it. And the more you shoot, the more you'll know what you can get away with. Next we have color. As cinematographers, the two main ways we have to work with colors are through color temperature and different combinations of red, green and blue light, which can be achieved by dialing settings on an LED light or with the use of gels. Let's first talk about color temperature. First, we have to understand that what we consider to be white light actually comes in many different tones. For instance, the white light you have inside of houses is generally a warmer, more orange white than the light that comes from the sun, which is bluer in comparison. These different gradients of warmth and coolness, orange or white to blue or white, is what's referred to as the color temperature of a light, and it is measured in kelvins. The lower the kelvin number, and the more orange the light will appear, while the higher the kelvin number, the bluer the light will appear. An easy way to remember that is to think of fire. The higher the temperature, the bluer the flame. The lower the temperature, the more orange. Despite all these different gradients of white, you'd most likely still see white as white if you were to carry around a piece of white paper across several white lights varying in color temperature, and that is because your brain knows that the paper should appear white and automatically compensates and adjusts its interpretation of colors for it to appear white. But your camera doesn't know that white should appear white under different color temperatures, and so you have the option to dial in the white balance. Matching your white balance in camera to the color temperature of your light will make white appear neutral, that is, without a shift towards orange or blue. All that your camera is doing when changing white balance is adjusting its sensitivity in the lower or higher end of the visible spectrum of light. When balancing to tungsten, or 3200 kelvin, the camera sensor becomes less sensitive to the higher end of the visible spectrum in order to pick up less of the red and orange which are overly present in tungsten lights. Likewise, when balancing to daylight, or 5600 kelvin, the camera becomes less sensitive to the lower end of the visible spectrum in order to pick up less blue light, which is more abundant in sunlight. So that's the technical side. How do you use color temperature creatively? For a start, you can balance your camera to the same temperature as the light that is most prominent in your scene, and then adjust the color temperature of the other lights accordingly. In this example, we balanced the camera to 3200 kelvin, which is also what we used for our key light, while this practical lamp was set to 2000 kelvin, and this shaft of light to 4800 kelvin, for a bit of color contrast. But you don't always have to match the white balance on your camera to the color temperature of your key light. For instance, with this light set to 5600 kelvin to mimic sunlight, you can either set your camera to 5600 kelvin, or set your camera to 4800 kelvin for a colder feel, perhaps a winter light, or perhaps set the camera to 6500 kelvin for a warmer feel. How about setting your camera to 5600 kelvin, but having your light at 4200 kelvin for a late afternoon feel? You can also set your light to 5600 kelvin, and balance your camera to 4200 kelvin for a bluish moonlight. In this example, we had industrial fluorescent tubes that we matched with our film lights by setting them to 5000 kelvin with a quarter plus green gel. We then balanced the camera to 3800 kelvin, in order to get this cyan tone throughout the scene. This cyan tone was then enhanced in the grade. Those are just a few examples, and I invite you to experiment and see what you like by dialing different color temperatures in your light and camera while lighting your set. Once you've set your color temperature, you can also change the color of your light by using a gel in front of it, or by dialing in the color or a gel preset if you're using an RGB LED unit. A gel essentially acts as a filter that cuts out part of your light spectrum. For instance, a primary red gel will only let red wavelengths pass through while cutting off all the other wavelengths. And because some of your light's wavelengths are cut off by the gel, your light will lose in light intensity, which is why you should not worry about light intensity until you set your light direction, the quality, and the color to your liking. Tweaking any of those three attributes will affect your light exposure, so save yourself some time and keep that light meter away until you're happy with those three. And once you're happy, then you can look at... Exposure There are many books and online resources that cover how to set up proper exposure as well as the mathematical relationship between T-stop, shutter angle, and ISO, so I'll skip that part. What I find more useful to look at in order to create compelling images are your key-to-fill light ratio and the foreground-to-background lighting ratio. Both key-to-fill light ratio and foreground-to-background ratio are expressed either in stops or in their difference in brightness. They both refer to the same thing, but it's a technical side note that is worth mentioning because different people would express this same concept in two different ways. First, we must understand that there is a doubling of or halving of the amount of light measured in lux or foot candle every time you open up or close down your lens by a stop. The same goes for dimming your light up or down by a stop. Opening up a stop on your lens might not look like the image is getting twice as bright to our human eyes, but that is only because our eyes and brain interpret light in a logarithmic way so that we too can fit in more visible stops at once and have a higher dynamic range. But mathematically speaking, you are letting in twice as much light into your sensor every time you open up a stop on your lens and half as much light every time you close down by a stop. So how can we use this concept creatively? Let's start with the key-to-fill light ratio. This ratio refers to the difference in brightness between the key side and fill side of your talent's face, namely the brightest side of their face that is facing the light and the opposite side, also known as the shadow side. What does your scene need? What key-to-fill ratio would serve the emotion you're trying to convey? Is it a 1-stop ratio, which is also called a 2-to-1 ratio because your key side is twice as bright as your fill side? Is it a 2-stop or 4-to-1 ratio? A 3-stop or 8-to-1 ratio? Or do you need 4 stops, or a 16-to-1 ratio? You'll notice that the brightness on the key side didn't change in these examples. That is because you'd usually want to set your key side first to a level that you like before controlling the fill side to your desired ratio. To make your fill side brighter, you can either use a bounce board or a fill light. What I usually find to look best and most naturalistic is a fill light above and behind the camera or slightly on axis towards the key and making it as large of a source as possible so that it appears non-directional and feels like ambient light, while pointing it down slightly to avoid casting shadows on the background or illuminating the background too much. Note that some of this fill light might reach into your key side and make that side brighter, in which case you'd want to balance that out by dimming your key light in return. And that's the reason why you'd often see this ratio called a key plus fill to fill alone ratio, which is more accurate. In order to make your fill side darker, you can use negative fill. This would usually be a 4x4 floppy at the very least, placed on your talent's shadow side in order to cut off any ambient light bouncing from walls and objects around them that would naturally illuminate and fill in their shadow side. The larger and closer the negative fill, the more ambient light you'd prevent from reaching your talent and the darker their fill side would get. Next we have our foreground to background lighting ratio, which measures the difference in stop or brightness level between your foreground, which is usually your subject, and your background. How dark you want your background to be in comparison to your subject would entirely depend on the effect you're trying to convey, but I find that having the talent be one stop to one and a half stop brighter than the background is a great way to make them pop out while keeping a natural feel to the image. There's a few things you can do on set in order to have the most creative control over your foreground to background ratio. First, whenever possible, you should have your key light and the light illuminating your background be separate in order to be able to control their individual intensity without one affecting the other. Second, you can discuss the blocking with the director in order to avoid having your talents land too close to any distracting background, such as bright walls. By having your talents far enough away from the background, it will be much easier to place your light in a way that illuminates them without lighting the background. Next, if your actors are sitting against a bed frame or a sofa that is against a wall, you can easily pull that bed or sofa 2 to 3 feet away from the wall to once again give yourself the space to angle your light on your talent but not on the wall. And in most cases, the compression of your lens won't make the gap visible on screen. Additionally, you can use snap grids and ecraits in front of your softboxes and diffusion frames to retain the softness of your light while minimizing the spill. And lastly, we have cut and shape. Once you've set the direction, softness, color and intensity of your light, you can then shape it to your liking by using flags. Here's a few helpful tips. First, you can use a flag on the side of your key light, also known as a sider, to control the spill of your key on the background. This is very helpful when working with larger sources. Second, the further the flag is from your light source, the cleaner the cut will be. That is because the further your flag is from the light and the less oblique rays of light will reach into the area you're trying to flag off. Third, if you're using any type of diffusion, you'll pretty much always want to place your flag between the diffusion frame and your subject rather than between your light and the diffusion frame. Not only will you get a cleaner cut, but you'll also be less likely to affect the softness and intensity of the area you're lighting by doing so. So there you have it, the five attributes of lighting that I hope will serve you as much as it served me. I've been using this framework for almost a decade and still rely on it today. Most importantly, I haven't found a faster way to work because following this order helps you minimize redundancy of action, and we all know that time is the most important asset you have on set. Well, in life in general too. So don't forget to follow this order when setting up your lights, experiment, and have fun!