Tuesday, 5 March 2013

Practiced based research - Lighting and it's types

Since working in a studio environment I've been looking into the different types of lights and their different effects. I also had a lighting tutorial in University to show them working and how their settings effect mood, tone, and shadow. It's been very helpful and useful to how different lights can effect photographs so dramatically. Since in previous photography all I ever really used was natural light. I wanted to research the different kinds and what their uses differ from each other for self reference.

All light can be divided into categories based on the type (source), the intensity, and the direction. One of the most basic divisions is between natural and artificial light. Another is hard versus diffuse (soft) light. A third set of categories distinguishes the direction from which the light is coming, which it also determines where highlights and shadows will appear in the image. Side, frontal, and back light are a few examples of direction. But, before diving into specifics, it’s important to understand the relationship of these categories to one another.

Natural Light
Natural light is the best type of light for many photographic situations. In fact, the broader goal for many photographers using artificial light is simply to emulate the qualities of natural light. One positive note on natural light: no batteries needed. It’s available anywhere you go and, apart from the subject matter, it’s probably the quality of the natural light that drew you to the scene in the first place. In short, the one reason why natural light looks so good in images is that it is natural.
As previously noted, natural light comes from the Sun (or other “suns,” in the case of starlight), and each type of natural light has its own qualities:
  • Full, midday sunlight versus early-morning or late-afternoon
  • Open shade
  • Overcast skies
  • Sunrise or sunset
  • The deep blues of twilight
  • Moonlight
  • Starlight
  • Window light
  • Reflected sunlight, both soft and hard
  • Daylight illumination from a frosted skylight
  • Other natural sources not from the sun include firelight and lightning
Natural light can also be great for photos of people, though it may sometimes prove more difficult to use because it requires careful planning and observation. It takes more skill to find the ideal natural light for the idea, emotion, or mood you wish to convey.
Learning to evaluate and take advantage of natural light will dramatically improve your photographs.

Taking Advantage of Natural Light: Time of Day
Pay close attention to the shadows, highlights and feeling of depth created in photos captured around 7:45 a.m. as compared with the photos captured around 7:00 p.m. The light used in the earlier image (7:45 a.m.) helps create more depth in the scene, and it helps provide the perception of more space between foreground, middle ground, and background. In the later image (7:00 p.m.), the light is not helping to create more depth. Spatially, the scene is “flatter” in terms of contrast, and thus has less depth.

"morning mist" captured by Robert Strachan
Landscape photographers are known to use the warm colors and long shadows of morning light. This can create more drama in the landscape, which may better represent the land itself. If you search for landscape images in magazines and calendars, you will find many examples of dramatic light achieved in early-morning hours. You will not see many landscape images made in midday light, because the increased contrast, lack of visual depth, and (unsaturated) colors are not what the photographer thought would best describe the scene.
Obviously, this is a generalization, but as you pay close attention to the thousands of images you encounter daily, you’ll likely notice trends in terms of the type of light used for different situations.

Taking Advantage of Natural Light – Disabling Your Flash

The one thing that can kill the ambience of natural or existing light is the on-camera flash. Though this is not as big of an issue when shooting in manual mode, semi-automatic and fully automatic modes (such as aperture-priority and sports modes, respectively) can trigger the flash.
The best thing to do is to turn off the flash in these modes. The camera is programmed to make a good exposure, and often that includes adding in some of its own light if it feels there isn’t enough available light for a good exposure. In some cases, the flash is triggered simply because it has been fooled by the presence of dark tones in the main subject or the background. This goes back, remember, to your understanding of how your in-camera (reflective) meter works.
Nothing can destroy the subtlety and character of natural light more than camera’s built-in flash. If you want to take advantage of natural light, learn how to turn off your camera’s built-in flash.

Artificial Light

Artificial light is any light that is not natural and depends on an external source of power. This could be your on-camera flash, external flash units or studio strobes, tungsten photo floods, an overhead light fixture, fluorescent lights in an office environment, streetlights, stadium lights, stage lighting for a concert, the twinkling glow from Christmas-tree lights, neon, and so forth. Like natural light, artificial light can fall under the larger category of existing or available light (in other words, light you do not bring to or set up for your subject).
You might decide to use artificial light for a variety of reasons, including:
  • When you need maximum control of your scene by using studio light sources, whether they are strobes or continuous hot lights.
  • When there is not enough natural light to make an exposure.
  • When you want to preserve the quality of the artificial light as an element in your image, such as the warm yellow light from a corner lamp, the harsh overhead from fluorescent lights, or the colorful glow of stage or club lights.

Photo captured by keenan butcher
 Experimenting with different types of artificial lighting will help you understand how they influence the image and how your camera records them. The more you know about the qualities of light, natural and artificial, the better you can visualize and control the effects they bring. Being able to identify different sources of artificial light and their inherent qualities will go a long way in helping you predict how they will affect your photography.

 Tungsten Lights
These are also referred to as incandescent lights. They are most often found in homes, and they are among the cheapest bulbs to purchase. However, they are much less energy-efficient, and they give off a good amount of heat. Light from tungsten bulbs can vary quite a bit in terms of brightness (25-watt bulb versus a 500-watt photo flood, for example), but this light is generally softer and warmer than fluorescent light.

Halogen Light
This type of incandescent light is more energy-efficient and produces a brighter, whiter light source. It is used in projectors, household lamps, some streetlights, car headlights, and continuous studio lighting (also referred to as “hot lights”).

Neon Light
A true neon light will have an orange-red color and is filled with neon gas, through which a small current is passed, causing it to glow. What we know as neon signs, which may be a number of different colors, rely on other types of gases for their color. Though neon lights don’t really provide enough illumination to be a light source for a broader scene, they themselves can make for interesting subjects or background material

Streetlight (Sodium Vapor)
Like neon lights, sodium-vapor lights use pressurized gas to produce light. You can identify sodium-vapor lights by their yellow illumination. If you take a long night exposure using street lamps as your light source, you’ll notice this same, somewhat eerie yellow-orange glow pervade your image.

 "Street Light" captured by Sway

Artificial Light (continued)
In addition to ambient or available artificial light, there are a number of options with which you can have more control: namely, flash or strobes. Many digital cameras come with built-in on-camera flash units that may automatically pop up, ready to fire in low-light situations (depending on your exposure mode and camera make). As alluded to earlier, these are generally the least appealing light sources in terms of effect..

Off-Camera Flash
An off-camera flash is more useful and offers many possibilities for positioning the flash, as well as for using accessories such as a mini flash-softbox or bounce cards to modify the quality of the light. In order to use an off-camera flash, your camera needs to have either a hot shoe or flash sync connection.

Club or Stage Light
Amazing effects can be achieved with these multicolored directional lights. Stage lights in particular are extremely powerful, making it easy to isolate separate beams of illumination. Concerts make liberal use of such effects

Studio Strobes
These are lighting systems that run from a power pack that is plugged into a standard power outlet. They connect to your camera via a sync cord, a slave unit (a device where an on-camera flash triggers the studio strobes), or a wireless connection. Studio strobes offer the most versatility and control in how the scene is lit. Their power output can be varied at the power pack, and they can accept a wide variety of light-modifying accessories.
As far as studio work goes, for the new user, the main disadvantage of a strobe system is that you cannot see the effect that the light will have on the subject. You have to use a flash meter to determine exposure and take test shots to determine how well the lighting setup is working. Fortunately, digital cameras provide instant feedback without the need for costly Polaroid tests.

   "Tanisha" captured by Vishwa Kiran

Lightboxes and Studio Stands
There is a wide variety of stands and softbox types. If you plan to shoot on-location, size and weight might be an issue, and if you plan to keep lights only in the studio, maybe size is not such a big issue. More important, though, is the quality of light provided by the various light-modification tools. There are many different shapes of soft boxes and umbrellas, and they all produce a different quality of light.
Tungsten-Halogen Lamps
Some portrait studios still use hot lights for various reasons. There are advantages and disadvantage to both. In general, these are all terms with which you should be familiar, and this knowledge will help you choose the right lighting for any situation down the road.

Hard and Diffuse Light
We used the terms soft and hard light several times to describe characteristics of individual artificial light sources, and, in the case of natural light, qualities relating to specific times of day. Certainly, all light can be divided into one of these two categories, also referred to as specular and diffuse light.

Diffuse Light(or soft)
light is lower in contrast and more even. As a result, it is often easier to achieve a good exposure for both highlighted and shadowy areas, as the difference between the two is slight. Diffuse light can be very complementary for pictures of people where that person’s likeness is the highest priority.

Diffuse light is either filtered through or bounced off another surface before hitting the subject. Open shade is one source of diffuse light. Other examples include: light filtered through a high canopy of leaves, the shady side of a building, or in the shelter of a doorway. Clouds, fog, dust, smoke, and smog are other environmental circumstances that can yield varying degrees of diffuse light, each serving to block or bounce the sun’s rays. Window light may also provide very soft light, depending on the direction of the sun or how dirty the glass
Hard Light
Hard light is directional and generally more intense, thereby heightening contrast. It’s great for building drama in a scene and emphasizing shape and dimension. Deep, defined shadows are characteristics of harsher light. Generally, hard light is used to illustrate an idea or concept, but it does not create a good likeness of a person.
Directional Light
The direction from which light hits your subject can have dramatic impact on your shot. Side lighting, for example, is quite effective at sculpting a subject, throwing long shadows, bringing out details, and adding a powerful flair. Backlit scenes can also be dramatic, with the light coming directly towards the camera, creating stark outlines of foreground elements or rendering a subject to complete silhouette. Frontal light tends to “flatten” a subject by minimizing the distance relationships between foreground and background and eliminating shadows that would otherwise give a sense of dimension.
The direction of light can also be used to slim a face or make a face look more full. For example, if your subject has a round face, you can use side lighting to give the perception that the subject’s face is not as round. For a thin face you wanted to make a little fuller, you could use more frontal light. The best thing to do is try many different combinations to see what you like and in what situations.

"sculptor" captured by Jan Michael Vincent V Castillo

Directional Light (continued)
Additional possibilities, though seldom used, as they are less flattering, include lighting a subject from above or below. Yet, even these have their uses. Lighting a subject from above may reference police questioning or interrogation, or even the sun at midday. Lighting from below may conjure the feeling of telling ghost stories around a campfire, with the story’s narrator holding a flashlight under his chin for eerie effect.
In addition to the direction of light, you can also play with how this relationship changes when your subject is not facing the camera, but instead facing away, or into the light.

Different lighting types and fixtures explained

arri junior 650The quality of light produced by either a natural or artificial light source is often categorized as Hard or Soft light. An unobscured sun or an undiffused Redhead for example are both hard light sources. These types of hard lighting sources reveals shape and texture and creates the overall modeling for your subject. Hard light gives the picture definition and vigor, and is essential to create a three-dimensional illusion. Hard Light refers to a point source of light, such as the sun or a single open-faced Redhead, which produces hard shadows. The best point sources are also very controllable, with the use of barn doors and projection attachments for example. Hard light can be used in many ways as it has a long throw, however, it does create dense and high contrast shadows that need to be watched as they can produce very unflattering results. Hard light is imminently necessary and desirable for some shooting situations, especially when you want to simulate intense sunlight or the crisp light of the moon. However, hard light has to be used carefully. Strong modeling and dramatic shadows will give your images a dynamic appeal but, if it is used badly or inappropriately, hard light can produce crude modeling and coarse tonal contrasts. For most of todays shooting situations, many Lighting Cameramen like to use at least some level of diffusion to give you that feeling of natural lighting. Even a light frost sheet of diffusion material attached to the barn doors of a fresnel will help create a more natural lighting effect.

kino floMost modern lighting is a subtle blend of hard and soft light. Although most key light sources are hard, you will usually want to control their shadows and tonal contrast by introducing a certain amount of soft 'fill light'. Soft Light refers to a light source that has a large surface area in relation to the subject, so that the light 'wraps' around the subject. In the past, lighting cameramen would achieved this effect by bouncing light off ceilings and walls, but this is now largely considered to be a very crude way of achieving soft light, as it is very uncontrollable and can end up producing very flat images. Soft light sources tend to destroy texture and are not so controllable as hard light so soft light sources are normally used to fill in the shadows and control the contrast created by the main key light, which would normally be hard. More common ways to create controllable soft light is to use softboxes; these are black fabric boxes with white diffusion material across the front, which converts the hard light source into a soft light source. dedolight softboxSoftboxes can be used with fresnels and open-faced lights such as Redheads and Arrilites. However, they do turn an inefficient light source into an even more inefficient one. The advantage of softboxes is that they produce a lovely soft light source and they pack away efficiently. However, setting them up and packing them away can be time consuming, especially when they have been on a hot Redhead for a few hours as the ring and other metal parts will be very hot and you will have to wait for them to cool down first; this partly offsets the portability advantage when compared to something like the fluorescent Kino Flo Diva-Lite, which produces a lovely soft light and only takes seconds to set up and tear down. The latter also has the advantage of being slim when set up, so it does not take up valuable shooting space. However, fluorescent units like the Kino Flo Diva-Lite have a very short throw compared to hard light sources, which means you have to move the lights in much closer to your subject. All soft lights can benefit from the use of grids (also known as egg crates). These grids enable the soft light to be controlled so that the spread of light is confined to the subject and does not spill all over the set.

arriliteA lamp that uses a tungsten filament. Also known as Hot lights. These are filament lights with the same characteristics as a domestic table lamp in a house, but usually a lot bigger. The biggest one currently in general use in the film market is 20,000 watts. This light is huge, but most portable solutions for mobile crews are no bigger than 2000 watts and with today's modern DV cameras a 1000-watt unit would be as powerful as you would want to go.

Colour: Nominally 3200K although it can vary, usually downwards towards 3000K

Advantages: Cheap to purchase and uncomplicated; like a household light, they plug directly into the mains so there is no need for an additional ballast (a ballast is similar to a power supply/transformer, except designed to limit amperage to a specific level). Comes in many fixture designs, some of which are very controllable. One of the most relevant ones available on the market today is the Dedolight, which also gets over many of the disadvantages such as short bulb life, long term costs, heat and inefficiency, while also providing astonishing lighting control, quality and flexibility.

Disadvantages: Hot to work with as barn doors get really hot. Because of their heat they can turn your environment into a sauna very quickly, which can make life very uncomfortable for your actors/presenters and create extra work for make-up artists as the heat causes foreheads to sweat. If shooting food, the excess heat can cause it to melt. Bulb life can be disappointingly short, ad this to the often expensive bulbs, and it all adds up to a very expensive long term purchase. Because it has a colour temperature of 3200K, when it needs to be used in daylight, a colour correction filter is required and up to half the light output is lost when you need it the most. Inefficient, Lumen-Per-Watt; this is the least efficient technology on the market today.

HMI (Hydrargyrum Medium-arc-length Iodide)
dedolightHMIs are arc lights contained in a sealed capsule.The HMI (and the MSR version) has a number of advantages over Tungsten lights. The main one being its incredible efficiency; it can produce five times the light output of tungsten light per watt i.e. more of its power consumption is going into the actual light output, as opposed to heat generation, which means less heat and less power consumption. Because it is a daylight-balanced light, it can be used to great effect outside as a fill in light to the sun. Again there is a huge range of HMI units available from 200w right up to 18K. The average size for the mobile crew is around 400w. HMIs require a special power supply known as a ballast. The role of the ballast is to limit eh amperage that runs through the arc. The ballast also outputs the correct voltage for a particular HMI globe and also includes special circuitry to 'strike' (or start) the arc.

Colour: Nominally 5600K daylight. However this can vary from one manufacturer to another and can also vary depending on the age of the unit and/or bulb.

Advantages: Great efficiency and because it is 5600K daylight balanced it can be used to full effect in the most lumen challenging environments. Low power consumption and less heat. Comes in many interesting fixture designs.

Disadvantages: Expensive to buy as it is a much more complicated unit compared to a tungsten lamp. Bulbs are pricey but life times are generally reasonable. A high voltage power supply or ballast is required to run the light, which adds a little to set up times and can also be heavy to transport.

kino floA very popular - and relatively new - addition to this list of lighting equipment are fluorescent instruments. Fluorescent lights are a phosphor based lamp technology, which relies on a number of elements to make them work well in a video/film environment. For many years they had a bad reputation for producing green spikes and irregular colour problems as well as flicker problems. These problems have now been overcome mainly by the great work of a Hollywood based company called Kino Flo. In the late 80s, Kino Flo introduced colour balanced tubes in both tungsten 3200K and daylight 5600K. The research and development of Kino Flo have evened out the nasty green spikes and eliminated any flicker at the same time. These units have all the advantages of regular industrial fluorescent lights; only without the sickly green spike or flicker. The Kino Flo Diva-Lite has a built in high-frequency ballast and dimmer. The Diva-Lite is a small lightweight portable unit that is very easy to transport, set up and pack away.

Advantages: Beautifully soft quality of light that wraps around its subject without the need for inefficient and space hungry diffusion solutions such as softboxes. Great colour with professional bulbs (Kino Flo) and available in both daylight and tungsten; so no inefficient filters stealing light when you need it most. Cool running, no heat, which keeps the subject cool as well as the working environment. Low energy, great efficiency (lumen-per-watt), which is why it is so cool. Fast set up and teardown times in comparison to some other soft light sources.

Disadvantages: More bulky to carry than a tungsten light with a softbox, this however can be out weighed by set up times. More expensive to buy than tungsten lights, but not as pricey as HMI units and ballasts.

kino floThere is no doubt that LED lights are the future. The advantages of LED lights are many, including: cold running, lightweight, compact, low power consumption, to name a few. 95% of the power sent to an LED light is transferred into actual light, whereas with a tungsten/halogen light, approximately 75% of the power is transferred into heat; great if you are heating your house, not so great if you are trying to light a set. Although LED lights are relatively new in the world of video and TV productions, they are fast making in-roads onto sets around the world. They are also very popular in corporate and location video productions due to their compact size and lightweight. Unlike tungsten filament lights, LED lights are cool/cold running; even when left on all day. There are many advantages to cool-running lights. Apart from the obvious health and safety advantages, they won't cook your talent on set. Because the technology is relatively new, prices are still a bit on the high side, also, the light 'throw' from LEDs is not as good as say a regular Blonde or Redhead light; but this is changing as technology improves.

Advantages:Cold running so no health and safety issues, no more burned fingertips or exploding bulbs. Low power consumption so can run off batteries all day. Lighter and more compact so easy to transport, set up and pack away.

Disadvantages: The 'throw' is considerably less than regular Tungsten lighting. Colour balance can be vague on certain cheaper brands so check with a colour meter before purchasing; regardless of what manufacture blurb tells you..

ianiro redheadA small portable mains powered tungsten lighting unit, usually 800 watts in power output. The Redhead is an open-faced light designed in the 1970's. It is called the Redhead because it was always (and largely still is) red in colour. Rumor has it that the inventor needed to use a plastic composite to build the heads out of, and red was the only colour he could get his hands on. Today, Ianiro and Photon Beard continue that colour tradition, Arri, however, now use the colour blue. By today's standards the Redhead is considered unmanageable i.e. it is a difficult light source to control and is even considered to be a little over-powered for modern DV camcorders that simply don't need that much lighting power due to their excellent low-light capabilities. The Redhead (by today's standards) is inefficient, runs very hot and the bulbs tend to have a short life and are also expensive to replace. However, the Redhead sometimes has its moments; for example when a volume of light is needed and finesse is not an issue; such as lighting a green-screen. Manufacturers include: Arri, Ianiro, Photon Beard, Strand.

arrilite 2000Blondes are the more powerful 2000 watt tungsten big brother of the Redhead and like the Redhead, the Blonde is an old open-faced lighting unit technology. The Blonde is named so because the colour of its case was always yellow (or blonde). They were called Blondes as kind of a follow up name to the Redhead; I guess somebody thought it would be a smart thing to do. These days not all Blondes are yellow in colour, Arri's Blonde (called the Arrilite 2000) is in fact blue. Like Redheads, Blondes will become very hot in operation, which can create a hot and uncomfortable working environment for your cast and crew. Like the Redhead, they are also very uncontrollable with just 4 barn doors to help shape the light. However, Blondes do have there uses when extreme amounts of light is called for. Although Blondes are an older lighting instrument design, they are still in wide use in many studios around the world today. Manufacturers include: Arri, Ianiro, Photon Beard, Strand.

FRESNEL (150 watt juniors to 20,000 watt large film lights)
arri junior 150Invented in 1822 by French physicist Augustin Jean Fresnel. The Fresnel light is a lensed lighting instrument and has been around for many years in many guises. It is an optical system designed to focus light efficiently. The Fresnel optical system is used on many different wattage heads and is an improvement in terms of control in comparison to Redheads and other open faced lights, but the Fresnel still does not get any where near the focusable control of a Dedolight, which uses two internal focusable lenses, as opposed to just one glass lens on the front. When used in tungsten heads the same issues apply as to heat verses wattage, which is not good, as power consumption can be an issue. However, the Fresnel lens lighting unit is in common use on all film sets where the bigger versions are a staple to the lighting professional. For the small crew Fresnels such as the Arri Junior range are a great option, they range from 150 watts to 650 watts. Other more efficient solutions are available, such as the Dedolight and the Kino Flo Diva-Light. Manufacturers include: Arri, Ianiro, Photon Beard, Strand.

dedolite dlh4Invented by the German DoP Dedo Weigert in the 1990's. Without doubt the most versatile and controllable hard light on the market today. It normally runs off mains but can also run off any 12v battery such as a car cigarette lighter socket. Don't let its small size fool you; this light will be the first one out of your car every time. With a spot to flood ratio of 1:20 (the next best technology is 1:6) a 150 watt Dedolight produces the same light output of a 500 watt fresnel on flood. On spot it has an incredible throw of over a 100 feet. The Dedolight also has a projector attachment system that uses gobos to throw many different focusable effects such as background patterns, venetian blinds, sunlight through trees etc. All of this comes at a price, but the Dedolight is very economical to run once bought and also has excellent bulb life and when they do eventually go, they only cost £3.50 each to replace. In January 2006 Dedo Weigert designed a brand new Dedo 'Soft Light'. There are a few options available with the new soft light, but the most popular model is the DLH1X150 Tungsten Soft Light, which is designed to fit inside the small softbox designed specially for it; you can also remove the front baffle diffuser from the softbox to get a harder light source with more spread as well as being able to buy an 'Egg Crate' to attach to the front of the softbox to make the soft light more directional. The new soft lights are available in 150, 300 and 1000 watt power outputs and start from £375 including softbox and inline dimmer switch. If you are buying for the long-term (unlike cameras, lights have a long working life) you could do a lot worse than invest in a kit of Dedolights.

kino flo divalite 400Kino Flo mastered perfect colour balanced 3200K and 5600K fluorescent flicker-free tubes in the late 1980's. A compact fluorescent lighting unit that consists of four 55-watt colour corrected bulbs in kit form for easy transportation. The advantage of this system is the speed of use coupled with a practical lightweight fixture design, and most importantly, the colour correct quality of light that it emits. The Diva-Lite can be bulbed with either tungsten or daylight broadcast quality bulbs, making it very efficient in all environments without the loss of light due to filters. It is also possibly the fastest way to achieve high quality soft light on location. Created by Kino Flo, who have an Oscar for their fluorescent lighting system.


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