“There are only two problems in photography. One is how to conquer light. The other is how to capture a moment of reality just as you release the shutter.”
-Edward Steichan
Photography is essentially the use of light to capture a moment of time. Without light photography (and life) wouldn’t be possible. This write up will help you understand and hopefully better your photography by the ability to make light work for you whether it be in the studio or in our world.
In our world there are various qualities of light that help reveal different aspects of a image. These qualities include; texture, form, shape, color, emotions, and moods. These are qualities we see everyday but many may not recognize it. This is what we photographers pride ourselves in, That being the ability to see these phenomena in our world around us.
In term of light quality there are two categories. The first quality is the comparative light which controls the brightness, color, and contrast. This type of quality is what you could manipulate after exposing the image. When you adjust contrast or brightness on Photoshop or even the darkroom you are playing with the comparative light quality of the image. Yet the next quality is something that CANNOT be manipulated after the exposure, and that is Formative light. Formative light is the specular, diffused, and direction of the light in the image and is difficult to measure. The human eye can see it but it is hard to explain. Formative light also has a major role in revealing space, volume, shape, texture, and dimension.
Within the comparative light quality, to start off, brightness. Brightness is the intensity or quality of light reflecting or radiating. This is measured in Lumens. With brightness there are three levels within the field; high key, low key, and medium key. A high key lighting is an image that is very bright and is considered feminine, next time you look at a make-up add look what color the background is. Often times the back is white and the subject is very bright, or high key. Next we have a low key image which is considered a masculine image. A low key image is dark. A medium key image would be one that is “normal” everyday scene, or earth tones. In another note “photography only interprets brightness quality and seldom duplicates it” (Bradshaw). It is important to understand that the human eye can only see 20 stops (stops as in the aperture of a camera) of light, film sees 8-10 stops of light, and paper will only see 4-5 stops of light. Now maybe you ask, “what about digital”? A RAW image can only see 6 stops of light.
The next important part about brightness is how to measure this. When you have light that falls upon a subject, that light is referred to as illuminance. light that is reflecting off an object is is called luminance. This is very important as the light meter inside of you camera is a luminance light meter and IS NOT correct to the proper exposure. This is the reason that professional photographers use incident light meters. By metering the light from the source you will render a subject, or scene a proper exposure. In order to correctly use the light meter in your camera you must learn how to use it.
Learning to use your luminance light meter you must understand how to use the ZONE system in order to properly render a scene and I will do another write up on that soon.
Understanding Zones link
http://www.superhonda.com/forum/show...20#post3050920
I’m pretty sure everyone knows contrast. Contrast is the difference between light and dark areas, self explanatory. A type of light that affects contrast is known as the ambient light, lumination which does not come directly from a primary light source. Ambient light has NO directional value and is NOT an available light. This ambient light also is what creates shadow detail in an image.
There are three types of formative light. First there is what is known as specular light, light that travels in a straight line from the source. Some examples of specular light include; flashlight, projectors, laser, household light bulbs, and even the sun. Specular lights, when cast on a subject, will project a sharp shadow. Next we have what is known as a diffused light, and generally the light source must be bigger than the subject to be considered a diffused light. An example of diffused light is light that is reflected from a building, grass, and sky. In contrast to the specular light, the diffused light creates soft shadows, places a strong emphasis on form of a subject, and helps hide texture. For example if you want to photograph a pool ball, the best choice of light would be a diffused light for the fact that the light will give the ball its round look. Lastly we have possibly the most important type of light and that is direction lighting. This light controls formation of shadows and helps place emphasis on texture, form, and a sense of spacial depth in the shadows.
When it comes to the surface of objects there are 2 types of surfaces. A Specular surface, such as a car body, reflects light. Therefore to best photograph a specular surface one would want to use a diffused light source to illuminate the subject. A Diffused surface absorbs the light much like, for instance, clothing. To properly shoot and expose a diffused surface you would want to use a specular light.
Lastly we have two more types of lighting that is used; emotionally passive and emotionally active illumination. Emotionally passive illumination is your flat, everyday lighting which create neutral color qualities, low contrast, and uniform moderate brightness. Emotionally active illumination is used to draw attention and has a strong directional quality coupled with strong contrasts. (specular lighting)
In photography, at least when it is not black and white, color has a major role in an image. Neutral color balance is the lack of color influence in any neutral tones. Collective color balance is the over all color balance within a scene, and this strongly depends on the type of film and light used. Local color is the color of objects and subjects and are expressed with localized lighting effects.
Color also has a large influence on emotion. Red (warm tones) is generally considered a warm, romantic color and is used for getting attention. With food the color red often implies the sense of something hot and/or sweet. Another set of colors would be those considered pastel colors. Pastels creates rich emotions and is popular amongst the older generations. Of course then we have the “cool” colors such as the blues and greens which create a soothing feel.
Within the studio different lights are used to light subject matter. The main source in a lighting scene is known as your key light. The key light can be specular or diffused and it establishes formation of shadows and highlights. It is normally the strongest lightin the scene. Then there is what is known as the fill light. Typically diffused, it simulates ambient light andis used to control highlight ratios. Lastly there is the background lighting which is used to control local areas within the scene. This helps seperate the subject from the background and add depth or the illusion of depth.
sources
Bradshaw, Robert. "Pho103 lighting notes." Brooks Institute of Photography March 16, 2006
Linear Mode
