Everyday when we open our eyes the first thing we see is light. Light is all around us. Right now you’re thinking “NO DUH!” well you need to rethink lighting. Lighting isn’t about some special hard to work with technique that only a few people know how to do. We see light everyday, and we can make any scene look exactly like we want it to, if we learn a few basic things about lighting. First of all study the light around you, look for Diffused light (any lamp with a shade on it), Reflective light (light bouncing off the walls) Hard light (any focused light) look for these types of lights, and how they effect your environment. See how these lights effect the mood of a room. Lighting is really about creating a mood or atmosphere. Lighting done well can make or break your scene.
A lot of new filmmakers become very anxious when it comes to lighting, and they usually leave it up to a Cinematographer or a Gapher. There’s nothing wrong with this, Cinematographers and Gaphers work with light everyday, and that’s why they are Gaphers and Cinematographers. As a MICRO-BUDGET FILMMAKER this is not a great idea. Control of the mood of the film is lost here. To be able to communicate to a Cinematographer and Gapher to make sure as a filmmaker you get exactly what you want. You need to understand, or at least know the language needed to communicate the feel you are going for. Besides all of that, lighting isn’t really as hard as everybody makes it out to be. If you’re a true Micro-Budget Filmmaker you don’t have the funds available for a Gapher or expensive lighting anyway. This Lesson in Lighting is geared toward someone who wants to learn lighting on a micro-budget, and it starts off with the basics. We will finish with advanced techniques that will WOW! Your audiences and impress your cast and crew.
Before we really get started on this lesson we need to define a few terms we’ll be using.
Study These Terms and refer back to these when needed.
Ambient Light - The light already present in a scene, before any additional lighting is added.
Incident Light - Light seen directly from a light source (lamp, sun, etc)
Reflected Light - Light seen after having bounced off a surface.
Color Temperature - A standard of measuring the characteristics of light, measured in kelvins.
Contrast Ratio - The difference in brightness between the brightest white and the darkest black within an image.
Key Light - The main light on the subject, providing most of the illumination and contrast.
Fill Light - A light placed to the side of the subject to fill out shadows and balance the key light.
Hard Light - Light directly from a source such as the sun, traveling undisturbed onto the subject being lit.
Soft Light(DIFFUSED LIGHT)- Light which appears to "wrap around" the subject to some degree. This light Produces less shadows or softer shadows.
Spot - A controlled, narrowly-focused beam of light.
Flood - A broad beam of light, less directional and intense than a spot.
Tungsten - Light from an ordinary light bulb containing a thin coiled tungsten wire that becomes incandescent (emits light) when an electric current is passed along it. Tungsten color temperature is around 2800K to 3400K. Also known as incandescent light.
Halogen - Type of lamp in which a tungsten filament is sealed in a clear capsule filled with a halogen gas.
Fresnel - A light which has a lens with raised circular ridges on its outer surface. The Fresnel lens is used to focus the light beam.
Incandescent - Incandescent lamps produce heat by heating a wire filament until it glows. The glow is caused by the filament's resistance to the current and is called incandescence.
Bounce Board – A reflector used as a fill light. The board can be made of plain white material, gold, silver, or any other reflective color to match the key light being used.
Now that you’ve studied the light around you and the definitions above, you are ready to learn how to control it, and make the light work for you.
We will discuss some lighting fixtures here, but we will go into more detail on types and brands of lights later, and which lighting fixtures are more affordable.
The first thing we need to understand is that our camera picks up light differently than our eyes.
Perceiving Light
When light enters the eye, it first passes through the cornea, then the aqueous humor, lens and vitreous humor. Ultimately it reaches the retina, which is the light-sensing structure of the eye. The retina contains two types of cells, called rods and cones. Rods handle vision in low light, and cones handle color vision and detail. When light contacts these two types of cells, a series of complex chemical reactions occurs. The chemical that is formed (activated rhodopsin) creates electrical impulses in the optic nerve. Generally, the outer segment of rods are long and thin, whereas the outer segment of cones are more, well, cone shaped. Below is an example of a rod and a cone:
Video Cameras Perceive light similar, but have millions less receptors, so the definition is less. Instead of Rods and cones cameras have pixels. SD video is 740x480 pixels per frame or .355 Mega pixels. HD video high end is 1920x1080 or 2.07 Mega pixels per frame.
A digital camera, such as a CCD based one, has 4 "receptors" that make up a "pixel" - red, green and two blue (the human eye is more sensitive to light in the blue end of the spectrum, so it has two receptors to get a more precise reading).
Human eyes have two types of receptors called "rods" and "cones". You have 4.5 million cones and 90 million rods. Now rods work better in low lighting conditions (i.e. night vision) but do not pick up color very well (if at all), whereas it is the c
ones that pick up color. It would be tempting to say that you have 4.5 mega pixels then, but that really wouldn't be accurate. You have 94.5 pixels, only 4.5 of which can detect color. But not all of the rods and/or cones are usable in all lighting conditions, so how many usable pixels you have varies quite a bit.
The analogy kind of breaks down because we are kind of comparing apples to oranges. Our eyes blow away camera lenses, as well as anyway we can conceive of recording those images on CMOS or CCD’s
THE LIGHTING BASICS
When we think of the above definitions, and we want to really understand how to apply them to lighting a scene the easiest way is to think about the shadow each light will cast. I know you’re thinking I don’t CARE ABOUT THE SHADOWS, I WANT TO LEARN HOW TO LIGHT A SCENE. The shadow a light casts is how each light is defined, so we will concentrate on the shadows for now. Hard light will produce a highly defined sharp shadow. Diffused or soft light will produce a soft shadow with no definition or possibly no shadow at all, depending on the amount of light, and distance from the light source. There are all kinds of different lighting techniques, but if you understand this basic reality of light it will help you understand the very basics of lighting.
Let’s talk about Daylight. The ultimate light source, and the cheapest light source we have available is the Sun. Lighting in Sunlight sounds easy, but it’s really not. For one simple reason you have no control over the sun. The sun produces different kinds of light during the day, and during the different seasons of the year. In the morning and in the evening the suns power is weaker, and the color temperature drops off sometimes as low as 1800K which is yellow Magenta, and may not work for a scene. Also during mid-afternoon when the sun is at it’s most powerful it may have a contrast ratio that produces so many shadows that all the actors look like raccoons from the shadows created from the brow ridge above their eyes. At mid-afternoon the color temperature could be over 6500k . Over 6500k is more than most Camcorders can record, and they default to white with no definition. White balancing Video cameras can only go so far. Most 3ccd Pro-Summer Camcorders only can work with light temperatures between 2800k and 5800k. Under 2800k the picture is yellow and magenta, and over 5800k it’s blue. On the next page is a Kelvin color chart.
Shooting in midday under a clear sky will not work. The light power of the sun is way to strong, and the color temperature is unusable. We need to knock the power of the light and the color temperature down, so we can shoot under the sun. This can be done by using a NEUTRAL DENSITY FILTER, and BOUNCE BOARDS on those days when it’s under 6500k. When it’s over 6500k or we just need to knock down that power even more we can use a SCRIM. A SCRIM is basically made out of the same material as screen doors, and it knocks the power of light down depending on how tightly the mesh is woven. It’s usually placed above the Talent or the actors to knock down the power of the sun. The scrim is basically causing the light to be knocked down, but also produces a shadow, and that can not been scene on camera in most cases scrims are hard to use unless we are shooting close-ups. The bounce boards are used to reflect the light of the sun at a different angle to the talent or actor basically to eliminate shadows on the face. Shadows on the face from the sun look terrible on camera, and can ruin a whole scene. The sun under overcast skies produces a pleasing diffuse lighting, and is much easier to work with. The shadows are diffused, and it’s much easier to bounce the shadows away. In the evenings and in the mornings anywhere from two to three ours from Sunset or Sundown is what the DGA (Directors Guild of America) and the CSA (Cinematographer Society of America) call golden hour. The light is weak and produces a gold color light. The amount of time from Sundown and Sunset that produces these golden hours depends on time of year and on location on the planet. The light temperature in Kelvin’s also depends on time of year and location on the planet.
All of the photos to the right were shot using the camera auto setting with no filters or manual corrections. Auto-WB, Auto-AE, Auto –everything.
Below is the proper way to set up a two shot in overcast sunlight.
For a Cost Effective approach, we will introduce the Altman Fresnel. This light is designed for use in theaters. It does not do well in RAIN, so DO NOT TAKE THIS LIGHT OUT IN RAIN..but this light can do everything the more expensive Arri's can do. We recommend this because we found it to be the best light for the money, and the light quality is virtually the same as the more expensive Arri's lights. Save a few bucks and get two or three of these...you can augment it with do - it - yourself lights, but have at least 2 or 3 of these ready to go at all times.
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