摄影三点布光技巧详解(英文)

Three Point Lighting: Learn How to Use the Key, Fill, and Back Lights Three point lighting is the standard lighting technique used in video. It’s a good idea to become comfortable with three point lighting because as a video shooter, you’ll find yourself using it over and over again.It has the power to transform an otherwise boring and flat image into a dynamic interesting image with a subject that “pops”.It’s not as difficult as you might think to use the 3 point lighting technique, and in this article, I’ll share with you what I’ve learned…Three Point Lighting Adds DimensionThe goal of three point lighting is to create the illusion of a three-dimensional subject in atwo-dimensional image. While you can create dimension a number of different ways, there’s no doubt that using light and shadow is a powerful way to accomplish this, and three point lighting is the lighting technique most commonly used.What are the three points of light we’re talking about?∙The Key Light– This is the main light used on your subject.∙The Fill Light– The purpose of this light is to fill in the shadows created by the key light, preventing them from getting too dark.∙The Back Light– This is used to separate the subject from the background.The Key Light is the Main Light in a 3 Point Lighting SetupWhen I’m arranging lights, I like to place the key light first be cause it’s the main one, and I use the rest of the lights to “support” the key light.The purpose of the key light is to put the light on the subject. You can place it anywhere you want, but a common placement is about 45 degrees to either side of the camera, and about 45 degrees up from the subject.Which side of the camera should you place it on? It depends on the look you’re going for. You can get as creative as you want with this. First, let’s cover the common placement of the key light, and then let’s cover some more creative fun placements.A good rule of thumb if you’re trying to create a standard look…Whichever way the subject is facing in the frame, put the key light on that side of the camera. Let’s consider an example. Imagine that you’re shooting video of a standard talking head, and they’re facing the left side of the frame. In this case, you would put the key light on the left side of the video camera as well.Incidentally, this style of lighting is called “short lighting” because if you divide the subject’s face in half with an imaginary line, this kind of lighting illuminates the short side of the face, leaving the broad side of the subject’s face (the side of the face closest to the camera) in shadow.If you were in an interview situation, you would place the camera first. Then have the the interviewer sitting to the left of the camera’s position, and then have the key light to the left of the interviewer (assuming the interviewer is off camera). This lights the far side of the subject’s face and causes your subject to look toward the left side of the frame, because that’s where the interviewer is.Key Light Placements: Creative OptionsIf you’re feeling creative, try placing the key light at different angles and elevations. You can put the key light off to one side of the subject, nearly straight out to the side, and illuminate only half of their face. This is called “side lighting” because…well…they’re lit from the side. If you’re shooting a film, you might use side lighting to symbolically represent the conflict the character is feeling. Or you could also just do it because it looks amazing, and then people will think you did it to symbolize conflict. (Accidental genius!)You could also try placing the key light at a high elevation, angled higher above your subject’s head but pointing down toward your subject. This placement would create deep shadows in their eye sockets —usually an undesirable look—but if you’re trying to make the subject look sinister for some reason, you might like this technique. Maybe you’re interviewing them for a documentary because they’re a prison convict, or maybe they’re a politician (couldn’t resist this one), and you want them to appear ominous.As viewers, we’re always intrigued when we can’t see the subject’s eyes. We don’t trust them. Or they might seem dead to us. (What else has dark shadows in the eyes and mouth? Answer: Skulls. Ooh.) While you’re at it, you might have a reason to place the key light low below the subject, and then point it up toward them. This lights the chin and the underside of the nose. It casts shadows in the opposite direction we’re accustomed to seeing them. Because it’s so strange, it makes the viewers feel unsettled.Think of all the times you told ghost stories in the dar k with only a flashlight under your chin. It’s a freaky look that can make your subject appear evil. Or just highly dramatic.You probably wouldn’t have to think too hard to come up with reasons for using this kind of lightingin a film…Two men plotting an assassination around a campfire, or one man threatening another man over a dinner table lit only by a candle on the surface beneath them. You get the idea. This can be a fun look to play with.Another frequent placement for a key light is behind the subject. This places the entire subject in shadow which we commonly call a silhouette. You can intentionally use this look to create a dramatic image, to keep the subject anonymous, or to de-emphasize the subject for whatever reason. Finally, another common placement —and the most boring— is right in front of the subject. The light might be directly above the camera, pointing toward the subject. This is called flat video lighting. It appears to widen the face, fills in shadows caused by wrinkles, and is the least dramatic style of lighting. This kind of lighting is sometimes called “glamor lighting” because on models it can enhance the look of their face, but my experience is that on most people, it just makes them look flat and boring, without character.So where should you put the key light? Anywhere you want it—depending on the look you’re trying to get. You have total freedom, so play with it and see what looks you like.The Fill Light: The Second Light in 3 Point LightingWhen you turn on the key light and nothing else, you might find that the overall look of the image is too dramatic and contrasty. There might be too many deep shadows. That’s where the fill light comes in. The purpose of the fill light is simply to fill in the shadows caused by the key light.One thing to be cautious about —the fill light should not create a second shadow. If you see two shadows, that means the fill light is too powerful and needs to be reduced.You can reduce the light a number of different ways. Some lights can be dimmed (for example, some LED and fluorescent lights) without changing the color temperature of the light. But it’s more common that you need to either move the light further from the subject, or put scrims or diffusion material over the light. You could also remove some bulbs or change the bulb to a less powerful one, but that means you’ll have to wait for it to cool off. That could take a while, so it’s usually faster to move the light away from the subject or put a scrim on it.Scrims are designed to reduce the light without softening it. They basically look like a net made out of metal. If you have professional video lights, you can probably purchase scrims as accessories for your specific video lighting equipment.You can also use neutral density gels to reduce light.These “gels” are semi-transparent gray sheets that you can put over the light to reduce the light without changing its color.Why am I spending so much time discussing reducing the intensity of the fill light? If you’re using a separate light f ixture for the fill light, then there’s a good chance you’ll end up wanting to reduce the light at some point. This seems to be a common adjustment for me. The look you like might bedifferent than the look I like, but I usually want some fill light in the shadows, but not too much — so I end up having to reduce the light.Other Options for the Fill LightYou don’t have to use a separate light as a fill light.If you’re trying to save money with your setup, this is a good place to do it. You can simply use something that reflects light from the key light and then bounce the light back toward the subject and into the shadows. This reduces the shadow darkness and creates the same effect as a fill light.Common tools for this are reflectors and white foam core boards. Reflectors are great because they tend to be very portable. Many of them collapse the same way a windshield sunscreen for your car might collapse. This makes them very easy to transport.White foam core boards are great because they’re inexpensive and they’re pretty stiff. If you’re using them to reflect sunlight outdoors, they don’t shake in the breeze the way a collapsible reflector tends to shake. The downside is foam core boards don’t collapse, so they’re more difficult to take with you, and the y tend to fall apart after a few uses. They’re not robust at all, so you’ll find yourself making frequent trips to the craft store to get new ones. (Hint — Buy a bunch at a time. I get mine for less than two dollars each.)But really you could use any reflective material as a fill light. You just want to make sure that 1) it doesn’t introduce any color into the shadow – which is why white foam core works better than green foam core —and 2) it doesn’t reflect too much light, which is why I would use a mirro r or aluminum foil as a key light and not so much for a fill light.It’s hard to go wrong with a fill light. Use it to fill in the shadows a little, or a lot, depending on the look you’re going for.Placing the fill light is pretty easy. It’s usually oppos ite the side of the camera from the key light. For example if the key light is to the camera’s left, then the fill light (or “fill source” if you’re using a reflector, which is a common thing) is off to the camera’s right.By the way, if you’re using a ref lector, you might need to get it in there pretty close to the subject without letting it show in the frame. This is where having assistants and C-stands can come in handy because it’s nearly impossible to hold the reflector in place AND operate the video c amera at the same time.The Back Light: The Third Light in 3 Point LightingI love back lights. I love the glowing rim they create around the hair and shoulders of the subject. I know many people argue against using them because in real life people don’t w alk around with a glowing halo around their head and shoulders. That’s true, but it doesn’t matter to me. I still love the look, and so I use it —unless I think I shouldn’t, and then I don’t.Here’s how you create a back light — You put a light behind your subject, usually suspended on the end of a horizontal arm attached to a C-stand or sturdy light stand (with sandbags on the base to keepit from toppling over). You place the light above their head and behind them so it points about 45 degrees down toward their hair and back.It’s extremely helpful to have barn doors on this light, so you can control the direction of the light and prevent it from accidentally spraying light in the camera lens. This would reduce the contrast in your image and maybe even create lens flare. That’s a problem you usually don’t want, so barn doors (or a snoot, if you’re feeling snooty —sorry, couldn’t resist that one either) can go a long way toward reducing spill light, which is light spilling into unwanted places, such as the camera lens. The only place you want this light is on the head, neck, and shoulders of your subject (for a talking head shot). How about a few tips and tricks for using the back light? Here’s a good one. Attach this light to a dimmer.If it’s a tungsten light, then as you dim it down, it will become redder, but that’s okay because this can actually look pretty awesome in a back light. Plus, you’ll find that controlling the intensity of this light is a common thing you’ll want to do. If the subject’s hair and clothing are dark, then you’ll have to really turn up the back light to mak e it show up at all. If their hair and clothing are light (such as a blond in a white shirt), then you’ll want to reduce the back light a lot.If you don’t want to dim it, you can also reduce the light’s intensity by dropping a scrim in front of it. Of course, you can also use the neutral density gel or diffusion paper I mentioned earlier. I usually use a combination of the dimmer with a sheet of diffusion paper, simply clipping the paper to the light’s barn doors with some clothespins. This softens the lig ht a little while also reducing the intensity.But once again, you should make these decisions based on the look you like. If you like blown out hair, then crank that thing up all the way. Just be careful, clients may not like it. ;)A Common Misconception with Three Point LightingThe truth is you don’t really need three separate lights to use 3 point lighting. Here’s a common technique that actually requires zero lights…Go outside in the late afternoon, early evening, when the sun is about 45 degrees up in the sky, and shoot video of a friend. Place your friend with their back to the sun, and you put your camera in front of them. With the sun behind them, they’ll have a beautiful glow around their hair and shoulders. This gives the effect of the back light in a 3 point lighting setup. The sun is the back light.Now have someone hold a reflector off to the side, out of the frame. Reflect some of the sunlight into your friend’s face (use the white side of the reflector, not the shiny mirror side —you don’t want to blind them!). This reflected light acts like a key light to model their face.What about the fill light? Nature will do its job. The sunlight will reflect off the grass, off the sidewalk, off the sky and clouds, creating an ambient light that will help fill in the shadows. See? You have now created a three point lighting setup without having to purchase any lights.That said, if you want full control over the lights indoors, you probably want to purchase (or rent) one light to be your key light, a reflector or a foam core board to be the fill source (fill light), and a separate smaller light to be the back light behind your subject.Three Point Lighting is That EasyJust like everything in video, the more you practice 3 point lighting, the more you’l l learn how to use it, and the more fun you’ll have experimenting. I encourage you to practice the traditional approaches, but also to play and have fun with nontraditional methods. For me, discovering new things is a lot of the fun of shooting video.。