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Section1 Introduction to

Whether you are lighting a stage or set, shooting still or video, using film, tape or solid-state media, proper lighting is essential to produce professional results. We are able to see because reflects off the subject we look at. Regardless of the type of camera you shoot with, with- out light, your subject will not be record-

SourceBook ed. Color, contrast, shape, and texture are just some of the attributes that are revealed through the effective use of light.

Lighting When you first consider purchasing , the choices can be overwhelming. The Lighting SourceBook is here to help you. This introduction will give you a basic understanding of lighting funda- mentals that will enable you to make intelligent choices. The B&H Lighting SourceBook is divided into sections cate- gorized by lighting fixture type. Each fix- ture type will be explained in detail at

the beginning of its section. The rofessional Photo, Video, Cine & Theatrical Photo, Video, P for LIGHTING INTRODUCTION TO LIGHTING

What Is Light? intimidated by the technical the products you may be used terms used in lighting are jargon. Unless you’re a physi- interested in. the foot-, and . Essentially, light is made up of cist, odds are you will not be wave-particles called photons. familiar with all terms listed, The Foot-candle is a standard refer- Watt Second Visible light falls in the nor do you have to be. A good ence unit used to measure the illu- This standard is used to mea- minance on a surface that is every- Electromagnetic Spectrum, light meter will provide you where one foot from a uniform point sure the total power potential between approximately 400 with all the information you source of light of one candle and of electronic power and 700 nanometers need. You may see light speci- equal to one per square foot. packs. One watt second is a (1 nanometer=one billionth of fications described in one of measurement of stored energy a meter). light consists the following terms: equal to one joule per second. of all visible colors combined. Foot Lambert The color of visible light Candela The Foot Lambert is a unit of Many factors affect the actual changes in respect to its wave- The candela (abbreviation, cd) luminance equal to the lumi- light reaching the subject and length. Red, being the longest is the standard unit of lumi- nance of a perfectly diffusing must therefore be considered. wavelength and violet, the nous intensity in the surface that emits or reflects The flash systems power pack shortest. A rainbow or light International System of Units. one lumen per square foot. simply stores the energy in passing through a prism Originally, luminous intensity capacitors that, when trig- demonstrates white light was measured in terms of Lux gered, release this energy being separated into its com- units called . This was Lux is a unit of illumination through the flash tube. ponent colors. based on the approximate equal to the direct illumina- Different flashes of similar amount of light emitted by a tion on a surface that is every- energy storage capacity will The Electromagnetic Spectrum candle flame. Late in the 20th where one meter from a uni- produce different amounts century, the current definition form point source of one can- and qualities of light. WAVELENGTH and terminology was adopted dle intensity or equal to one Choosing equipment solely on to allow for consistent and lumen per square meter. 300 its watt second rating will not repeatable measurements of give a true representation of its light. The term candela also Lux is a term commonly used light producing capability. The 400 refers to candle power, 1 can- to show the minimum amount quality and optimization of dela = 1 candlepower. of light needed for a video camera to function. Many the design of the flash tube 450 BLUE video cameras are so sensitive, and reflectors contribute sig- Candela is formally defined as the that they require small nificantly to a system’s overall magnitude of an electromagnetic field,

VISIBLE LIGHT 500 amounts of light to function performance. in a specified direction, that has a -3 properly, and are referred to as power level of 1/683 watt (1.46 x 10 It is impossible to accurately 550 GREEN W) per steradian at a frequency of 540 “low Lux cameras”. terahertz (540 THz or 5.40 x 1014 Hz). assess the quantity and quality One lux is the equivalent of of a system until the stored YELLOW 600 1.46 milliwatt (1.46 x 10-3 W) energy in its capacitors are of radiant electromagnetic (EM) converted to usable light in the ORANGE Foot-candle power at a frequency of 540 terahertz flash tube and focused by the 650 14 The Foot-candle is the mea- (540THz or 5.40 x 10 Hz), imping- on the subject. The RED surement of light output in ing at a right angle on a surface whose area is one square meter. A narrower the angle and the 700 NANOMETERS candela per square foot.

INFRA-RED frequency of 540 THz corresponds to more polished the reflector, The Foot-candle is used fre- a wavelength of about 555 nanome- the more light will be directed 800 quently to quantify the ters (nm), which is in the middle of toward the subject. amount of light present in a the visible-light spectrum. given area. In the B&H When comparing products SourceBook, many of the Lumen you must take into account lights will list the photometric A unit of equal variations in manufacturers Light Measurement data next to the light. The to the light emitted in a unit specs. Reflector angle, reflector There are many ways to mea- unit the light is measured by solid angle by a uniform point finish, flash tube color temper- sure the quantity and quality is in foot-candles. The photo- source of one candle intensity. ature, flash to subject distance, of light. Of course, a unit of metric data will enable you to ISO etc., must all be equal measure is essential. Don’t be compare the performance of NOTE: The most commonly before comparing specs.

8 www.bhphotovideo.com PHOTO - VIDEO - PRO AUDIO INTRODUCTION LIGHTING TO LIGHTING

Guide Number Inverse Square Law Aperture Shutter graph out of focus so that the Electronic flash units with fixed This is an important law that Setting Setting viewer’s eyes are immediately reflectors are usually rated with governs light intensity as a drawn to it. As the aperture a guide number for a specific function of distance. The law F1 1 decreases, (higher F number), ISO (usually ISO 100). The states that the quantity of light F1.4 2 the depth of field increases, guide number is used to calcu- giving you the ability to con-

is inversely proportional to the MORE LIGHT LESS MORE LIGHT LESS F2 late the lens f/stop setting for a 4 trol the range of foreground square of its distance. F2.8 good flash exposure when both 8 and background focus. the ISO rating of the film and Examples: A light is placed 1 F4 the distance from the flash to foot away from the subject. If F5.6 16 ISO the subject are known. the distance is doubled to two F8 30 ISO is an international stan- feet, the square of its distance dard to indicate the relative To determine the f/stop need- 2 is (2 ) or 2x2=4. The inverse of F11 60 sensitivity of film to light, also ed, divide the guide number 1 4 is ⁄4. Therefore, the quantity F16 called . Film speed is by the distance. To determine 125 of light at 2 feet from the sub- expressed as an ISO number the distance that can be illumi- 1 F22 ject is ⁄4 the amount of light at 250 or an exposure index (EI). ISO nated, divide the guide num- 1 foot. If the light is moved to F32 ratings have replaced earlier ber by the f/stop. 500 a distance of 8 feet, the square F45 ASA and DIN standards. 2 1000 When working with guide num- of its distance is (8 ) or F64 The higher the ISO number, bers, be sure to use the same 8x8=64. The inverse of 64 is 2000 1 F90 the more sensitive or faster the units of measurement in your ⁄64. The quantity of light at 8 1 F128 4000 film. The lower the ISO num- calculations (meters or feet) as feet from the subject is ⁄64 the ber, the less sensitive or slower specified by the guide number. amount of light. given time. They are the film. Film with a relatively Inverse Square Law expressed as a specific size of high ISO rating requires less Factors Effecting Exposure an opening in the diaphragm light for proper exposure than (iris) of a lens in proportion a lower ISO rated film. Shutter Speed to its focal length. F-stops A camera’s shutter speed set- exist in still, film, digital, and Example: film with a speed of ting determines the time peri- video cameras. ISO 100 is slower than a film od light is allowed to strike with a speed of ISO 200 and the film or image sensor. The The higher the F number, the requires twice as much light to shutter speed number is cali- smaller the opening. Each con- record the same exposure. brated in fractions of a sec- secutive higher number lets in Many cameras automatically 2 f/stops less illumination ond. The larger the number, half the amount of light of the set the film speed by reading a on background the shorter the exposure. 1 preceding number. The lower 1 the number, the larger the code on the film cassette. Film than on subject equals 1 second, 2 is ⁄2 sec- 1 opening. Each consecutive speed must be set on exposure ond, 4 is ⁄4 second and so on. lower number lets in twice the meters to obtain the correct Each increment represents exposure readings. half the exposure time of the amount of light of the preced- ing number. previous setting. The ISO prefix and the older ASA speeds are numerically Higher shutter speeds stop The lens aperture also con- trols depth of field. Depth of the same. For example, if the movement, whereas slower speed of a film were ISO shutter speeds will cause a field is the distance range that appears to be in focus in front (ASA) 200, you would set 200 blurring effect when shooting on the ISO (ASA) dial of your of and behind the film plane. fast moving subjects. camera or meter. 6´ from light to subject As the aperture increases, 8´ from light to F-stop (smaller F number), the depth Exposure Meters background F-stops, also known as aper- of field decreases. This would A good meter is essential in less than 1 f/stop tures, or lens openings con- be ideal if you want the sub- order to arrive at and maintain Illustrations courtesy of trol the amount of light pass- ject in focus and the rest of consistent exposure. Even if Norman Enterprises, Inc. ing through a lens at any the elements in the photo- you choose to shoot with

ORDER & INFORMATION (212) 444-6641 • FAX: (212) 239-7770 (800) 947-7008 1-800-947-9941 • www.bhphotovideo.com 9 PHOTO - VIDEO - PRO AUDIO LIGHTING INTRODUCTION TO LIGHTING , a meter will advantage of an incident meter 18% gray value. On the other If you are working with a help in controlling the detail is the fact that it measures the hand, if you were to fill the handheld spot meter, you and contrast of your images. quantity of light from the camera frame entirely with the would have a very precise Your exposure will be accu- source, regardless of the tonal man wearing the white suit, angle of light measurement as rate, and you will save time in range of the subject. the camera’s meter will try to small as one degree. This gives post-production. A bonus is darken the exposure, to once you greater accuracy in choos- consistency that adds profes- Incident again arrive at the 18% (medi- ing the specific tone the light sionalism to your work that Measurement um) gray value. reflects off, to arrive at your will surely be noticed by your exposure. clients. An other advantage of Even when the light source is using a hand held meter is the the same, the different reflec- Gray Card ability to achieve repeatable tive values of blacks and An 18% gray card is used effects when you wish. You , will cause the expo- when you want to achieve can choose your depth of field, sure to vary substantially proper exposure without hav- with a reflective metering sys- ing an incident meter. Since lighting ratio and produce Incident Reading high quality results every time tem, resulting in inaccurate the camera’s meter is trying to you record an image. readings. arrive at an average 18% in the White first place, if you fill your cam- Reflected Incident Light Versus Plate era frame with the gray card in Reflected Light Measurement front of your subject, the cam- Light radiates from its source, era’s meter will give you the whether it is the sun or an Gray proper exposure for this card, artificial source, such as an Plate thereby producing an average incandescent light. Light exposure that should be quite reflects off the subject and accurate. enters our eyes so that we are Black Types able to see it. The reason we Plate see black as black and white as Reflected Reading (Luminaires) white is that white surfaces Illustrations courtesy of reflect all the visible spectrum, Mamiya America Corp. White There are many different light- whereas black surfaces absorb Sekonic Professional Division. Plate ing fixtures that change the most of the light making it quality of the light that is gen- Example: appear dark to our eyes. erated by the inside. In Two subjects a man in a white the B&H SourceBook, you will Incident light is light that trav- suit, and a man in a black suit Gray see a majority of the different els from the source to the sub- are sitting next to one another Plate popular types used today. We ject and is measured before on a park bench. It’s a bright have defined a few of them for reflecting off the subject. Light sunny day, not a cloud in the you so you’ll get a good idea reflected off the subject is sky. The same amount of sun- of what each of them does. light is illuminating both sub- Black called reflected light. Plate jects equally; therefore the In addition to the sun, light Most camera metering systems exposure should be the same can be created many differ- measure reflected light. The for both subjects. Illustrations courtesy of Mamiya America Corp. ent ways. camera measures the light Sekonic Professional Division. after it has already reflected off The reflective metering system the subject. Spot meters are in most cameras tries to aver- With an incident light meter, used at the camera position to age the exposure to an 18% the light source has not Incandescent Lamps measure small areas of light (medium) gray. If you were to changed so the exposure will An incandescent light bulb reflected off the subject. fill the camera frame entirely be exactly the same for the works by heating a solid fila- with the man wearing the man in white and the man in ment so intensely that the fila- Most handheld meters feature black suit, the camera’s meter black. The tonal values in the ment’s both incident and reflected will try to lighten the expo- blacks and whites will be includes large amounts of visi- light measurement. The sure, in order to arrive at the reproduced accurately. ble light.

For Any Inquiries Regarding Your Order, Call Our Customer Service: 10 (800) 221-5743 • (212) 239-7765 • FAX: (800) 947-2215 • (212) 239-7549 PHOTO - VIDEO - PRO AUDIO INTRODUCTION LIGHTING TO LIGHTING

Fluorescent Lamps lights provide an even beam Softlight Controlling Light A fluorescent tube contains with good shadow definition. vapor that is ionized Fresnels are some of the After covering the quantity by an electrical current flowing most popular lights used in of light and where it comes through the tube, which is film and television produc- from, we need to discuss how then transformed into visible tion around the globe we are going to change the light by striking fluorescent quality of light in order to phosphors that coat the inner Open Face achieve optimum results. A general term for a surface of the tube. Light coming from a point luminaire A softlight is an indirect light- Gas Discharge Lamps that does source will be very specular ing source in which the light (undiffused - hard shadows) A gas discharge lamp is a not use a bounces off an internal reflec- lamp often filled with high- lens. They in nature. There are different tor to produce soft light with ways to diffuse (make light pressure mercury, sodium sometimes soft shadow edges. vapor, xenon or even neon may be pro- softer – soften shadows) light that is excited by an electrical vided with a Ellipsoidal to make it softer. safety glass or charge to produce visible A rule regarding the quality a wire mesh. light with specific color char- of light is: the larger the light Generally they acteristics. source and the closer it is to cast a fairly wide beam. They the subject, the softer the The typical electronic flash are excellent lights if you are light will be. Bouncing is constructed from going to diffuse them through off an umbrella for example, glass or quartz and comes in a silk, softbox, or bounce makes the light source a variety of shapes. The tube them off a reflective panel. change from the size of the is filled with the inert gas They tend to be a little lighter bulb to the size of the xenon. Electrodes are in weight and less expensive umbrella, making it bigger attached to each end of the than Fresnels. tube. Applying a high and diffusing the light. These fixtures are usually clas- Similar effects are achieved pulse to the “trigger” elec- Par sified as spotlights. They usu- trode on the tubes surface, A generally by bouncing light off a wall ally throw a controlled narrow or other large surface. ionizes the xenon gas in the lightweight beam with a sharp edge with luminaire flash tube. This makes it con- strong shadow definition. You can also pass light that uses a ductive and permits the tube through a diffusion gel, a PAR to discharge the stored ener- large diffusion panel, or a (Parabolic Cyc light gy held in capacitors in a softbox. In each case the light Aluminized fraction of second, produc- source is now the size of that Reflector) lamp. ing a powerful burst of light. modifier, in turn making it The light beam larger. The modifier scatters Fixtures characteristics depend upon the light so that it comes the type of lamp used. These from all directions filling in Fresnel types of luminaires are used Fresnels are all the surface angles of the frequently in stage and theatre identifiable subject thereby reducing the productions. by the glass contrast significantly. lens with the A fixture designed to provide concentric Broadlight an even wash of light on Light Modifiers circles on the A wide-angle cycloramas (a curved curtain front of the floodlight. or wall used as a background There are many ways to modi- fixture. Used to direct of a stage set to suggest fy the light reaching the sub- Fresnels are true a large amount unlimited space) and back- ject. They include umbrellas, focusing lights of light at a drops. The cyc light can also reflectors, light banks, soft due to the fact relatively large be used as a multi-purpose boxes, filters, diffusers, grids, that the lamp and reflector area. flood or fill light for stage and baffles etc. Creative lighting move in unison. Fresnel studio lighting applications. has almost no limits, thanks to

ORDER & INFORMATION (212) 444-6641 • FAX: (212) 239-7770 (800) 947-7008 1-800-947-9941 • www.bhphotovideo.com 11 PHOTO - VIDEO - PRO AUDIO LIGHTING INTRODUCTION TO LIGHTING the diversity of products avail- The chart illustrates, when the See the chart of Light The color wheel illustrates able. The appropriate section Balancing filters and their shift how complimentary colors of the B&H SourceBook will Kelvin increases, in degrees Kelvin. work. Note on each side of the go into greater detail describ- light becomes cooler, bluer. color wheel is the opposite or ing the full range of light mod- Conversely, as Kelvin temper- Warming Filters complimentary color. For ifying tools to help you ature decreases, light becomes For The Camera Shift (°Kelvin) instance if the light source is achieve just about any lighting warmer, more orange. This 85 5500k - 3200k green, add magenta filtration effect you desire. explains why, daylight film 85 C 5500k - 3800k to correct it. If blue, add yel- (balanced at 5500k) that is 81 C/D 5500k - 4500k low to correct it. And if red, exposed indoors with an 81 A/B 5500k - 4900k add cyan to correct it. Light and Color incandescent light source We use a term called “Light (3000k), will produce pho- Cooling Filters The easiest and most accu- Balancing” to describe how tographs that appear orange. rate way to determine which warm or cool the light is (usu- For The Camera Shift (°Kelvin) filter to use to correct your ally referred to in degrees 80 A 3200k - 5500k Kelvin for color balance is to use a color Kelvin). The other term is Common Light Sources 80 C/D 3200k - 4100k 82 A/B 3200k - 3500k meter. “Color Correction” which Source Degrees (in °K) deals more with pure color. In Clear blue sky 10,000-15,000 The advantage of digital image Digital image capture facili- order to achieve accurate color Overcast sky 6000-8000 tates color correction through results, you must have the creation, video or still, is that Sunlight, noon the use of image editing com- light balanced and color cor- you are able to white balance high altitude 6500 puter software. Naturally, rected. or correct the color tempera- Sunlight average 5400-6000 ture electronically. starting with the right color Electronic flash 5400-5600 balance, saves time. Light Balancing On-camera flash 5400-6000 Color Correction is mea- Daylight blue sured in degrees Kelvin. The If you have ever taken a pic- Lighting Placement flood lamps 4800 color temperature of light is ture of someone with daylight and Definitions Studio photo floods 3400 measured by taking a black film in a room lit by fluores- Studio bulbs 3200 or 3400 body radiator (an object or cent lights, you will have Key Light Studio quartz bulbs 3200 or 3400 system which absorbs all inci- noticed that your photos have The principal or main light Household lighting 2500-3000 dent radiation upon it and re- a green cast to them. Light- source that defines the overall 200w bulb 2980 radiates that energy back out), balancing filters will only look and the mood of the sub- 100w bulb 2900 When the black body radiator make this color cast warmer or ject 75w bulb 2820 is heated to a certain tempera- cooler. The only way to elimi- 60w bulb 2800 ture, it starts to glow orange. nate a color cast is to use the Fill Light 40w bulb 2650 As more heat is applied, the opposite or complimentary If you place a light source at Single candle 1200-1500 temperature increases, getting color of that cast to neutralize a 45-degree angle from the it. In this case, a magenta (the bluer (less orange), more To balance the light for this camera position and slightly opposite of green) filter of the towards white light and even- situation, we can either put a above the subject, you will same intensity of the green tually when the black body blue gel on the light to remove create a shadow on the other shift is used to cancel the radiator gets to the upper heat the orange, or attach a blue fil- side of the subject. The func- green effect. levels, it becomes even more ter to the camera lens. tion of the fill light is to blue, until it won’t change reduce this shadow creating a Additive and Subtractive anymore. This color is then In summary, light balancing Primary Colors flatter more balanced expo- compared to various light sure on both sides of the deals with the warm or cool MAGENTA sources, and assigned the tem- aspect of the light (color tem- subject. perature of the black body perature). With this knowl- BLUE RED radiator when heated to that edge an overcast day can be Background Light color. The following list dis- made to look sunny or a sun- These lights are directed at the plays some common light set can be made to look like background to add a sense of CYAN YELLOW sources with their average midday, simply by choosing separation between the subject color temperatures. the appropriate color filter. GREEN and background.

12 Equipment Leasing Available PHOTO - VIDEO - PRO AUDIO INTRODUCTION LIGHTING TO LIGHTING

Back Light Bulbs should never be (Separator Light) touched by bare skin. Grease Back lights are directed from skin can cause the glass towards the subject from to weaken. This weakening behind, adding separation may lead to shortened lamp between the subject and life and/or explosion. Bulbs background. These lights should be handled with tend to give a fringe of light paper, , or cloth to that surrounds the subject. avoid contact with skin. Back lights are also used to highlight a subjects hair. Almost all light fixtures pro- vide some kind of protective Rim Light screen or glass to cover the This light is usually used for front part of the fixture. It is lighting objects instead of rare for lamps to explode. people. However, in the instance that one does, there will be red- Kicker hot shards of glass flying The kicker is used to light the through the air after what side of a subject usually from a sounds like a gunshot. The low angle located behind and safety features are there for towards the side of the subject. your protection. It is well Most strobes also include This type of lighting will pro- advised that you use them. Three Point Lighting modeling lights to provide a duce a very flat light that is The traditional starting point preview of your lighting very clean without much Whenever a fixture is mount- to light a subject is three-point effects. The main thing to con- drama. If the ratio is 2:1, the ed from above, a safety cable is lighting. Basically, one light is centrate on is exposure and key light will give you twice an inexpensive way to insure located at 45 degrees to the controlling the lighting ratio the amount of light as the safety. If the light were to camera, this is the main or key of the different luminaires. fill, creating a slight shadow come loose from its mount, light. The fill light is posi- on the fill side of the subject. the safety cable will support tioned 45 degrees to the cam- Lighting Ratios This is one of the most com- the weight of the fixture, pre- era on the other side, and the Ratios are commonly used to monly used ratios. venting injury until the prob- is placed on a boom express the difference between lem can be fixed. just slightly behind and above the amounts of light on one When in doubt, start with a the subject’s head. side of the subject and the 2:1 ratio to see how it looks When lighting is used in pub- other. This ratio is usually on your subject. If the ratio lic places, seek advice from a The diagram illustrates the expressed in numerical form were 4:1 you would have a qualified gaffer or other light- basic positioning of three- starting with the key light in main light with four times ing professional. This is a great point lighting. proportion to the fill light. the amount of light as the way to make sure all local elec- fill, creating a greater shadow trical and safety codes are Three-point lighting is only For example: on the fill side of the subject. complied with. the starting point, but by no If a ratio is 1:1, it means that means must you light your the fill light is the same As you increase the ratio Conclusion subjects in this manner. It is intensity as the main light. between your key and fill As you continue through the always good to start with a lights, you will be adding B&H SourceBook, you will proven method to get the feel RATIO TABLE - F-STOPS more shape, and produce of things. Once you feel com- KEY FILL RATIO more dramatic results. find more in depth informa- tion to help you become a fortable with the results you F11 F11 1:1 lighting expert. Each section is are getting, you can become F11 F8 2:1 Caution packed with helpful guides more creative with your light- F11 F5.6 4:1 Before you continue to the rest and lighting instruction, so ing set ups. The beautiful F11 F4 8:1 of the B&H SourceBook, there make sure you review the thing about lighting is that you F11 F2.8 16:1 can see your results as you set are a few points about safety B&H SourceBook from cover F11 F2 32:1 up your lights. that need to be addressed. to cover.

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