Lesson 1: UNDERSTANDING LIGHT Lighting is a key ingredient in defining a successful photo. Without light, there would be no photography or life as we know it. Think of how light affects the world around us. The landscape is shaped by light and gives you a visual story in showing the layout of the land by defining textures within the landscape. In the studio, lighting for a portrait provides you the visual information about that person, the color of their hair, the shape of their face, and the color of their eyes, and tells us who they are. Lighting is used very successfully in photographing products in which the photo entices us to buy a product. Lighting techniques make food look better to us, a car more appealing, a model sexier. In this lesson we will discuss a variety of different types of light, light quality, and light direction. Understanding light and how it works is a vital aspect of creating great portraits. As photographers, we are working with basically two types of light; available light and light we create. Available light is known as Ambient light. This is light that exists and is constant. Sure, in some cases, it is light we can turn on or off, but it is usually a continuous light source. It could be sunlight, light from street lights, light from lamps in our living room, and lights in an office or manufacturing plant. But it is always the light source that is constant and can also be looked at as the light that you may not have control over its adjustment. Supplemental or secondary light is strobe (flash) or ‘hot lights’. Strobes are flash lights and hot lights are constant lights. In both cases, you can set up these lights and move them in or out of your photo setup. Strobe lights are by far the most commonly used type of supplemental lights used in portrait photography. Strobe lights also have the ability to change the output of the light emitted during each flash by an adjustment of the power settings. Hot lights can also be adjusted by a control making brighter or dimmer, but this also changes the color temperature of the light as the power is reduced. Strobes emit a flash that is instant and does not vary much in the amount of time that it is on. There is no such thing as bad light, only light used improperly.-Andreas Feinenger LIGHT QUALITY: SOFT VS HARD The quality of light is described by how hard or soft the shadow created by the light source is. Soft light and hard light are determined by the size of the light source in relation to the subject. Generally, the larger, more diffused the light source, the softer the light quality and shadows. If you have hard sunlight on your subject, the shadows are going to have hard edges like the scenic photo above. When the clouds cover the sun, a huge diffuser has been placed over the light source and the shadows become softer. When you place a diffuser in front of a hard light source and close to it, the shadows cast by the subject are as hard as if the diffuser wasn’t used. The farther you move the diffuser away from the light source and closer to the subject, the softer the shadow edges become. The idea here is that the larger the light sources in relation to the subject, the softer the light. Notice when the diffuser is placed next to the strobe, the diffusers effect is non existent as indicated by the hard edge shadows on the products. However, when you move the diffuser away from the light and close to the subject the shadows and contrast are soft. LIGHT QUALITY: FLAT VS CONTRAST Flat light has a shorter relationship between highlight and shadows. Imagine white and black objects against white. If the light is soft and diffused (flat) there will most likely not be a black shadow or a pure white highlight. Contrasty light has a more extreme range between shadow and highlight. The same subjects with hard light as the light source will probably have a pure black area in the shadows and a white highlight. This example represents the difference between flat and contrasty light. Notice the white cup is gray in the flat light and white in the contrasty light. LIGHT DIRECTION Light comes from all directions and as such creates a variety of different lighting looks. Light direction controls the shape of shadows. It’s these shadows that define the shape, texture, and form of our subjects. Direction defines the difference between shadow and highlight. Light direction comes from all angles and sides, but is usually defined as side light, backlight, front light, top light, etc. This example represents lighting angles. From left to right; frontal, 45 degree, side (90degree) and back light. ANGLE OF INCIDENCE The Angle of Incidence of light is an important concept in lighting and should be understood because its cause and effect will be experienced. When a light source emitting light reaches an object at a certain angle, that light is then bounced off the subject at the same angle. If the sun is at a point in the sky where it shines a specular highlight on a surface of water at a 45 degree angle, then the light bouncing off that water surface will be at a 45 degree angle as well. Imagine that you are taking a picture of your friend in front of a window. When you take the picture your flash has just created a glaring hot spot in the window behind your friend. This is because the Angle of Incidence is equal and at the same angle from light source to the camera. If you moved to the left or right and move your friend accordingly, you can move the reflection caused by the Angle of Incidence out of your frame. In the next examples you can see the Angle of Incidence principal at work. Even though this is a product photo, the theory applies to portraits. If you are asked to photograph an executive on location in front of his office window, you will have to deal with your lights reflecting in the glass. The hot spot on the phone and table top illustrates how light hitting a surface bounce off at the same angle. By moving the light back, the Angle of Incidence has also moved back off the phone. INVERSE SQUARE LAW This is another important fact about light. The illumination of a light source varies inversely by the square of the distance from the source. Huh? When you move a light source away from the subject, the light falls off. If you have a light source three feet from your subject and move it to six feet from your subject, the light fall off will not be by half, but rather be 25% of the original light value at 3 feet. The umbrella was placed 3’ from the product in the left photo and moved 6’ from the right photo. Notice that the light fall resulted in a dark picture. CONTROLLING FLASH AND AMBIENT The rule: Shutter speed controls Ambient light, f/stop or aperture controls flash. This can be difficult to understand, but is really quite simple. The shutter speeds on your camera controls the length of time that light is allowed to expose the picture. F/stop or aperture only controls the amount of light that exposes your picture. Think about it this way: draw a time line depicting how long a shutter speed is. Let’s say that 1/60 of a second is depicted as 3 inches long, then 1/125 would be 1.5 inches long because it is half the amount of time that 1/60 is. 1/30 would be 6 inches long because it is double the time that 1/60 is. This relationship is the same no matter what shutter speeds you use. ------------------------------------------------------------------- 1/30th second --------------------------------------- 1/60th second -------------------- 1/125 second The flash spike is 1/300th to 1/500 on average. This example is only meant to illustrate a point and is not proportional. When your flash unit fires a flash, that flash duration is usually somewhere around 1/300 to 1/500, depending on the make and model. So if you use 1/60 of a second on your camera and you take a picture with the flash, that flash duration of 1/300 of a second is just a spike in the middle of the time the shutter is open for 1/60 of second. It would also be a spike in the middle of 1/125, 1/30, etc. The flash fires for an instant within the time your shutter is open and no matter what the shutter speed is, the flash remains the same. As you can see, the shutter speed cannot control the brightness of your flash because it controls the time that ambient light hits the film and your flash is instant. Note: Different cameras with focal plane shutters have different Flash Sync shutter speeds for using flash. It averages about 1/125th but can be 1/60th on some cameras and 1/200 on others. This designated speed is the fastest shutter speed that you can use flash with. If you use a shutter speed faster than the designated sync speed, your film will come back with a horizontal split where half of the picture dark and the other half normally exposed.