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Lighting Equipment Primer for Beginners |
Note: This is not intended as a comprehensive guide to buying lighting equipment. It is targeted towards the photo hobbyist looking for an economical way to get started with studio lighting.Photography isn't rocket science but it does involve many independent variables which can confuse the beginner. Those who do not yet understand the nature of light are likely to make some poor choices when buying studio lighting gear. The soft diffuse indirect light from a north facing window is exactly the type of lighting you may spend a thousand dollars or more to duplicate in your basement with umbrellas or softboxes. It will provide a valuable baseline for comparison with artificial lighting. So before buying any artificial lighting equipment I recommend taking a few hours to master the basics of lighting using window light before making the jump into buying studio lighting gear. Window light can produce portraits with stunning clarity and simple elegance because the light is soft and falls off rapidly isolating the subject's face from the background. Learning by window light costs little more than one's time and can save a lot of time and money. You might decide you don't need studio lights after all, and if you do buy them you will already know how to use them effectively. I have a window light tutorial which shows how to position the subject, camera and background to achieve the same flattering short light pattern in full-face, oblique and profile views. Transitioning from Hot-Shoe Flash to Studio Lighting Single flash on camera: Most people who transition to studio lighting have experience with a single hot-shoe flash on the camera. The only real corralation between it and studio lighting is the fact that the flat shadowless lighting a hot-shoe mounted flash produces are the qualities desirable for the fill light in a two-light key/fill scenario. I'd recommend those who have only used a single flash master portraiture by window light before buying any additional hot-shoe flashes. I'd also recommend buying a bracket and buying or building a reflection diffuser if you are not already using one for single- or dual-flash. Multiple hot-shoe flashes: If you already own two or more hot-shoe flashes you know their limitations: lack of modeling lights, limited ability to modify the light, and recycle times. I learned the dual flash technique with manual flashes using distance to regulate the desired lighting ratio. The TTL flash systems today, such as the Canon 580ex provide wireless control of the lighting ratios, but he ratio nomenclature and the results those ratios produce are different than those used with manual studio lights and incident metering. Those already using dual flashes and lighting ratios should keep that in mind when ratio are mentioned in my tutorials. I would also recommend that users of multiple camera flashes try window light as a transition to studio lighting so they will be able to compare it soft light and smooth shadow transitions with both the results obtained with the camera flashes and the studio lights when they start using them. A Studio Lighting Gear Primer This is not an encyclopedia of all lighting options and equipment in the universe, just those a budget minded hobbyist might consider in these categories: flash heads, flash head modifiers, light stands, backgrounds and supports, light path modifiers, metering and test targets, and convenience features. Flash Heads Early designs for studio strobe lighting consisted of one or more central power sources which would sit on the floor and connect to multiple flash heads via cables. Later "mono-light" designs combined the power sources with the flash tube into a single compact unit light enough to be mounted on a light stand. There are advantages to both approaches, but nearly all hobbyists and pros alike opt for mono-lights. How they work: Light is produced from a glass tube filled with xenon gas which glows brightly when a high voltage electrical charge is passed through it. In a flash head the wall outlet voltage is stepped up to several thousand volts and stored in a device called a capacitor which is capable if gradually accumulating a charge then releasing it instantaneously to excite the flash tube. WARNING: the voltages and current in a flash head are lethal. Do not open or attempt repairs to your flash equipment. This warning also applies to hot-shoe flashes Flash heads may have incremental power settings such as full, 1/2, 1/4, etc., or step-less settings via a dial or slider. The actual output of the flash head is regulated by the charging level of the capacitors. To fire a flash at full power the circuitry of the flash head fully charges them. At less than full power the charging current is cut before the capacitors reach full potential. If power levels are decreased the capacitors to "dump" some of the stored potential into large resistors. Some flash heads do this automatically, others require firing the flash or pressing a "dump" button. When adjusting power down or up I find it is a good practice to fire the flash and let it build up to the desired new level before taking a meter reading. Price vs performance There is a huge range in price for studio flash equipment. All will create a bright white light which will expose an image. It is up to each purchaser to determine which brand and model meets their needs and budget. The key differences between brands, models, and price points are:
How much power do I need? That's usually the second question the beginner asks. (The first is what brand should I buy?). There is so much marketing hype surrounding power output measurements such as Watt-Seconds and how it relates to light output that the best approach for a beginner would be to narrow down their choices to a few brands they are interested in then solicit actual performance information from users on Internet lighting forums. Keep in mind that it is the working distance between subject and light, not the size of the studio which should dictate power needs. If you plan to shoot head and shoulder portraits on dark backgrounds your key light will typically be about three feet away regardless of whether you are shooting in your basement rec. room like I do or a barn. If you plan on shooting full length shots on white backgrounds with normal perspective you'll need a studio space which is a minimum of 30 x 40 feet and much more power. Light modifiers As in all things you need to know your tools so you can pick the best one for the job at hand. The goals for different styles vary and if you plan to shoot a variety of styles you'll need a wide variety of modifiers. Any light source will produce a pure white or pure black. The character if its light is defined by what is in between; how smooth or abrupt the highlight-to-midtone shadow transitions are. The highlight to mid-tone transitions are the most important for portraiture because the front of the face contains tones only in that range. Three variables affect the character of the light. The apparent size of the source, the distance from the subject, and the transmission / reflection characteristics of the modifier.
Umbrellas - Really two lights in one! Umbrella provide diffuse light which produces soft shadows and smooth highlight-to-shadow transitions. Silver umbrellas widen the area of coverage of a direct flash but do not change the character of the light in the same way a white one does. Light from as silver umbrella will produce more abrupt highlight-to-shadow transitions and specular reflections on shiny surfaces which are a distraction in conventional portraits but ideal for fashion and glamor where texture of clothing and sparkling look is desired. Both will light all over the studio. That's not a problem if you are shooting on a white or high-key background where light shadows are desirable, but is on dark backgrounds where control of the light is critical for creating attention grabbing contrast. Softboxes are a necessity for controlling the light, but umbrellas are very inexpensive so there is no reason not to own both. White umbrellas with a separate black cover are ideal for portraits. When light is bounced into them the black cover prevents spill. The cover can be removed an the umbrella reverse to fire the light through it, producing light which is diffuse but with a hot spot in the center. Bouncing the light into an umbrella also create a hot shot in the center. The hot spot is the main difference between a white shoot through umbrella or "brolly" box and a true softbox. The hot spot created by the shallow bowl shape of the umbrella creates two different intensities and character from the same modifier. The light bouncing from the center is brighter and the rays more parallel than the light from the outer edges. A photographer who is aware of the subtle differences can either aim the hot spot on the eye area, or anywhere else maximum attention is required creatively, or in on a high-key background aim the hot spot on the side of the face so the front remains slightly darker and contrasts more. Softboxes: The primary advantages of softboxes are control of both the hot spot created by the flash tube and unwanted spill. Softboxes come in many shapes but the basic design consists of a parabolic shaped fabric enclosure with the light source attached at the back via a metal ring known as a "speed ring" because is allows quick swapping of the boxes. Some of the light from the source passes directly through the diffusion panels but the rest is bounced around inside the softbox then reflected forward by the parabolic shape. There is a translucent panel on the front of the softbox and one or more additional diffusion panels used inside to control or eliminate the hot spot caused by the flash lamp. The inner surface of the softbox will affect its characteristics. Deep parabolic softboxes will produce more even light than flat shallow ones because the front panel is further away from the flash tube. A white liner will produce the most even distribution across the front surface whereas a silver liner will do the opposite, but provide higher efficiency. In some applications such as product shots the softbox type, size and inner diffusion is adjusted for each shot to achieve the desired appearance of the highlights and highlight-to-shadow transitions. Fabric grids an louvers are attached to the front of softboxes to control spill and make the light slightly more directional. Fabric grids are referred to as "egg crate" grids due to the similarity in size and shape between the cells in the grid and cartons used to ship bulk quantities if eggs. Louvers are vertical slats which only restrict the spread of light horizontally, they are typically deeper that grids and have a greater effect on the light. Both will cut the output of the light. Other flash head light modifiers: Beauty Dish: A beauty dish looks like a shallow metal bowl with a metal plate over the center close to the flash tube. Some of the light hit the dish directly from the tube but most hits the disk and bounces back into the dish then towards the subject. The light is diffuse like a softbox but produces reflections which are more specular. The advantage of the design is that it is compact and can be used very close to the face, which produces soft but very rapid transition from highlight-to-shadow. There is a comparison of the dish vs med. softbox in my tutorials. Metal Grids: Metal grids are used over standard reflectors to restrict the spread of the light. Most have a hexagonal "honeycomb" pattern with the size of the cells used to control the spread. They are typically marked according to the angle of dispersion; e.g., 10-degree. Narrow grids are typically used with hair lights, wider ones to selectively illuminate just the center of a background, or any other applications where a spot light effect is desired. Snoots: A reverse cone shaped modifier which restricts the beam of light. Typically used as accent lights and most effective on high-key backgrounds to help guide the eye of the viewer in the opposite direction from where they are aimed; towards the darker front of the face. Accent lights on dark backgrounds can become distraction from the front of the face and should be used with good judgment. Barn Doors:This is a device which attaches to a standard (direct) parabolic reflector. Door-like hinged flaps on the sides, top and bottom allow the light to be selectively blocked from an area. For example, when used in conjunction with a gridded hair light the lower flap might be hinged up to prevent the light from hitting the shoulders of the subject. Gels: Tinted mylar sheets which change the color or intensity of the light. Color gels, when used with a neutral white, gray or black background allow its color to be changed with the background lights. Neutral density gels will reduce light output without affecting its color and are used when too much flash head power restrict the use of wide apertures. Color correction gels are used to match the color temperature of light sources when shooting interiors or other situations where a combination of strobe and ambient light are used for the overall exposure. For example a CTO (orange) would be used to match the color of strobes to tungsten, and FLD to match to florescent ambient light. Diffusion gels can be used to diffuse a direct light source. For example a diffusion gel used in combination with a grid in a hair light would result in a more diffuse but still highly directional light source. The Rosco web site is a good source for gel information. Light Stands: There are many different brands, shapes and sizes of light stands to choose from. Here are the characteristics which differentiate one from another:
Standard sizes for stands are 6, 8 feet and 12-13 feet. The larger size should be used for studio lights because their wider footprint provides stability. The smaller stands are ideal for holding reflectors, test targets and other light path modifiers. You can never be too rich, too good looking, or have too many light stands. Booms: A boom is a horizontal arm extending from a light stand used to suspend a light without the stand being visible. Typical applications are hair lights or butterfly style key lighting in portraits, or product photography where the use of booms make exact positioning of the lights easier. The limiting factor for the use of a boom is ceiling height. If the studio space does not have ceilings higher than 8 ft. it is difficult to position a light on a boom above a standing subject. There are three styles of booms available:
Smaller, shorter booms are also available for use with lightweight 6-8 foot stands for positioning light path modifiers such as reflectors, flags, gobos and scrims which are described below. Rail Suspension Systems: The most elegant solution for positioning lights and eliminating the tangle of stands and cords is a ceiling mounted rail system. These are expensive and require enough ceiling height for mounting, but in an era where people build a $20,000 room to watch a DVD to save the cost of a $12 movie ticket, a rail mount system is probably not out of the realm of what some home studio builders might want to consider before spending several hundred dollars for stands. Because the tracks limit range of motion they not completely eliminate the need for light stands, but they are great way to position camera axis fill and hair light Backgrounds Backgrounds are like building a personal clothing collection. You need to start with the basics and build from there based on your needs and personal tastes. The basics are black, white, and medium gray. Background lighting, if controlled separately, can be used with and without gels to create a range of color and tone. What is used for a plain background really doesn't matter as long as it is smooth. Even a few wrinkles aren't a problem as they can easily be fixed in Photoshop, but that should be the exception not the rule. For beginners a trip to linen or fabric store in the U.S. can solve the basic background needs. A flat black king size sheet can be found for about $20 at discount outlets and 9- and 10- foot wide white cotton muslin fabric is available for about $7 per yard. The muslin can be used as is, dyed, or painted with latex house paint. One the best ideas I've seen for an inexpensive but durable seamless background is to buy a remnant of seamless flooring material and paint the reverse side gloss white. Wide rolls seamless paper and a wide selection of are available from photo retailers and online auction sites. They also carry and infinite variety of dyed and painted designs. The quality and accuracy of what is ordered from many low-end sources varies greatly and it is best to use advice from satisfied customers. Hand painted scenic backgrounds are also available. They are far more expensive but the quality is evident in the portraits taken with them. Background Supports The method used to suspend a background van be as simple as hanging a sheet from the ceiling with a curtain rod or pipe and some wire, or and elaborate motorized remote controlled wall mounted roller system. Most portable systems feature two sturdy light stands and an expandable cross bar. A popular wall mount design uses compression plugs which fit inside each end of a 2" metal or PVC pipe allowing up to three backgrounds to be raised and lowered via a chain drive similar to a window blind. Light path modifiers: Reflectors: Reflectors are utilized for fill with window light or when a single light is used in the studio, or for any other application where additional light is needed. Three colors are commonly used:
Flags, Gobos and Scrims: The even diffuse light produced by umbrellas and softboxes is a blessing when it falls on the face but a curse when it spills on a dark background or clothing which needs to be kept darker to create contrast with the face. A problems faced anyone attempting to shoot on a white background in a small studio is that the flare from the background enters the lens and giving the shadows a washed out look. Both problem can be remedied by using a modifier between the light source and the subject. When used close to the light the object will produce very shadows with soft edges. When used closer to the subject than the light the shadows created will have sharp edges. These devices are used for product photography to control the appearance of reflections on glass and shiny objects. For example, when for shooting watches appearance of the highlights and shadow detail is controlled by positioning the lights to provide necessary overall illumination (mostly light from the background) with the appearance of the highlights controlled by the placement of white and black cards around the objects. Three commonly used light path modifiers you will see mentioned are:
Light Measurement Digital cameras require correct exposure of the highlights because overexposure obliterates highlight detail. The camera histogram in the camera can be a valuable gauge for exposure, but only when the scene photographed has a white object of known characteristics in it. The camera exposure histogram cannot be used for setting lighting ratios because separate measurement of each light are required. Test Targets: Every serious photographer should have a card or other device for setting custom white balance and a standard test object to be used to verify correct exposure.
Incident Flash Meters: Incident meters read the light hitting an object. From it the meter calculates the average amount of light which will reflect from an average subject back into the lens of the camera. The meter can also be used to read the light intensity from different light sources as it hits an object. From the differences in intensity ratio of reflected light and be inferred. For example two lights of identical strength hitting a face from the camera axis and from the side will produce a highlight and shadow pattern on the face in which the highlights are twice as bright as the shadows where the two lights overlap: 1 key + 1 fill : 1 fill = 2:1 reflected highlight: shadow ratio. I have a tutorial devoted to ratios. Everyone should read it and their meter manual because everyone seems to have their own metering technique but there is really only one which is correct: the one outlined by the manufacturer in the manual. The one I use is from the Sekonic L-358 meter but most other meters are similar. Spot Reflective Flash Meters: Ratios are inferred mathematically when incident readings are taken and assume that neutral fill is always used. If you don't use neutral fill the ratio will not be even across the entire scene and the only way to measure it is with a reflection spot meter. A reflection spot meter reads only a narrow area, typically 1 degree of the field of view. The narrow field allows precise measurement of highlight and shadow areas to determine the ratio between them. But the exposure reading cannot be obtained from either spot reading. To use the reflective meter for exposure a reading must be taken off a "middle" gray target such as a gray card. I can also be determined with simple testing from the highlight reading using a bracket test to find out how many f/stops below the highlight spot reading produces a correctly exposed file. If that makes no sense, you don't understand how a meter actually determines exposure. Meters only measure light and at best they can only approximate what the camera sees. The best measuring device for exposure and rations are your eyeballs. When it looks right to you, it is right to you. Bear in mind however that a more experienced set of eyeballs might suggest that what seems right to you could be improved. Don't get defensive, just try what they suggest and let your eyes decide. Other Accessories In addition to the equipment listed above which produce, modify and measure the light there are plethora (a whole bunch) of devices which can be purchased to control and fire the lights remotely. Remote Controls: Some lighting systems allow remote control of the flash head power from a central control panel. This eliminates the need for running from light-to-light to set power when setting ratios. Its much easier to stand near the camera, remote control in hand and control the lights until the desired effect is determined via the modeling lights. Then meter readings can be taken to determine exposure and verify the intensity of accent lights not easily adjusted by eye. What remote control options manufacturer offer varies, so if this convenience feature is desired it should be factored into the overall purchasing decision for the flash heads. Wireless Triggering Systems: The PC connector and cable became the standard for connecting flash to camera 50 years ago and photographers have been tripping over PC cables and smashing cameras and lights on the floor ever since. The tyranny and tragedy of cables can be avoided for a price, which varies depending on the type and quality of the device:
Summary:This equipment primer doesn't cover all the possible studio equipment options or presume to know what is best for you. The best way to get an understanding of what is available is to visit the sites of major on-line retailers such as Calumet Photo and B&H Photo. B&H also has a very extensive print catalog containing studio lighting gear.To keep my editorial opinions of of the primer I've prepared a separate document to discuss the equipment choices I've made.
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Holistic Concepts for Lighting
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