determine  which  method  provides  the  best  results  under various  conditions.  The  method  you  choose  to  light  the same subject separates you from the average snapshot shooter (fig. 5-27). Off  Camera  Flash Some of your best flash pictures can be made with the flash unit off the camera. Holding the flash off the camera and above the lens tends to throw the shadows down and behind the subject. This is a good way to minimize distracting background shadows that occur when a subject is standing close to a wall. A flash held high above the lens, either left or right, makes the viewer less conscious of the flash illumination. People are accustomed  to  seeing  things  lit  from  above,  and  by placing  the  flash  above  the  subject,  it  closely  resembles the lighting of the sun or ceiling lights. Light that is far enough off the camera to illuminate the  subject  from  an  angle  produces  modeling  or roundness. This type of light creates the illusion of a third dimension-depth-and is more pleasing to the viewer than the two-dimensional flat effect you get with direct, front lighting. Light from an angle can also be used to bring out the texture of a subject. Indoors,   two   factors   are   important   when determining the modeling and texture effects you will get: first, the surface of the subject itself; second, the way you light that subject. To illustrate these points, try photographing a Ping-Pong ball and a tennis ball together. When you use direct, front lighting, your picture records a two-dimensional visualization of height and width, but little of roundness, depth, or texture. When you light the balls from the side, both acquire the illusion of depth; however, only the tennis ball  reveals  texture.  The  Ping-Pong  ball  is  much smoother  and  is  almost  textureless. Now substitute a young child and an old person for the balls. With frontlighting, most of the lines and wrinkles in the old person’s face will be minimized by the evenness of the light; however, when lighted from the side, almost every crease will become a shaded area and the ridges will be highlighted. Thus the texture of the old person's face is emphasized. The child, on the other  hand,  when  side  lighted,  is  still  almost  textureless just as in the case of the Ping-Pong ball. LIGHTING  RATIO Lighting ratio can be considered as a measure of contrast.  Lighting  ratio  refers  to  the  combined  intensity (at the subject) of the main and fill lights as compared to the intensity of the fill light alone; for example, both the main and fill light of equal intensity are shining on the subject. A reflected light meter reading is taken off an 18-percent gray card at the subject position that indicates there are 100 units of light falling on the subject. Now, with the main light turned off and the fill-in light still illuminating the subject, the reflected meter reading indicates there are only 50 units of light falling on the subject; therefore the lighting ratio is 2 to 1. Lighting ratio is usually expressed as the comparison of two light intensities, such as 1:1, 2:1,3:1, and so on. The largest number in a lighting ratio indicates the most intense illumination at the subject position; for example, a 2:1 ratio indicates the most intensely lighted portion of the subject (highlights) is receiving twice the amount of illumination as the least intensely lighted portion of the subject (shadows). The light that produces the most intense illumination is called the main, key, or modeling  light. The light that produces the least intense illumination is called the fill, or fill-in. A fill or fill-in light, as the name implies, fills in and softens the shadows  produced  by  the  main  light. Because a lighting ratio is a comparison of the combined main and “fill light” illumination intensities to the fill light illumination intensity alone, the fill light must be in a position so it completely illuminates the portion of the subject visible to the camera. This requires positioning the fill light close to the lens. As a rule, 3:1 lighting is considered the best general lighting  ratio  for  both  black-and-white  and  color photography. This 3:1 ratio provides normal contrast between the highlights and shadows and produces good natural-looking   photographs. Some  automatic  electronic  flashes  allow  you  to control  the  output  of  light.  When  set  in  the  manual position, you can adjust the light output by changing the intensity of the flash unit to 1/2, 1/4, 1/8, 1/16, and so forth. This allows you more control of flash-to-subject distance  as  well  as  aperture  (depth  of  field)  control. Achieving  the  desired  lighting  ratio  with  an automatic flash unit where the flash intensity can be controlled is quite easy. To achieve a 2:1 ratio, you set both flash units at the same distance and at the same intensity (either full power, 1/2, 1/4, and so on). To achieve a 3:1 ratio, set both flash units at the same distance and set the main light flash at full power and the fill flash at one-half power. A 5:1 or even higher lighting ratio can be obtained by setting both flash units at the same distance and the main flash at full power and the fill flash at one-fourth power, and so on. In order to 5-34