Our PhotoSmith Talks About
LIGHT
by Mark Smith
When asked by the editors to contribute a regular column to this magazine, I was at first stumped by what to write about. When I saw the credentials of all the other writers, I felt compelled to write something they too might find interesting, as well as you readers, which meant it might have to be somewhat advanced, and then I realized the other columnists are all writing advanced articles too, and those who are just learning about photography would appreciate some coverage of the basics, and so that shall be my role, to cover the basics of photography. Now, where to begin? Why, at the beginning, of course!
I consider light to be the most important aspect of photography. After all, the word photography means "writing with light." It seems fitting with the first issue of this magazine that we would explore light.
Light can be more easily studied if we break it down into several elements all of which contributed to the whole but in different ways. The first and most important element of light is direction. The direction is generally referred to with respect to the subject. If we say a subject is front lit then the light source is striking the front of the subject and the shadow from that light then falls behind the subject and out of view of the camera. Two good examples of the use of front lighting would be putting the sun over your shoulder to illuminate your subjects (any of you youngsters remember that instruction?) and using flash on camera for snapshots or I.D. photos. I'm sure all of you who drive or have a passport, have a marvelous picture of yourself taken with this style of lighting. While front lighting might not be the preferred direction for portraits, it is ideal for I.D. photos where you want to show all the information of the subject necessary for identification. If you do want to show shape, textures, or form, then sidelighting is perhaps the best choice. This direction (coming from one side of the subject) will cause a shadow on the opposite side of the subject to achieve this. Successful nature photographers utilize this direction of light to achieve dramatic landscapes. Another direction of light is backlighting. While this direction casts its shadow toward the camera and can cause metering problems and lens flare (a lens hood may be helpful for this), this is a good choice for portraiture because it creates a "glow" around the subject, especially subjects with full heads of hair. It also works well for translucent subjects, such as flowers, as their brightness level will appear to increase .
The next property of light is its quality and there two possible extremes: hard and soft. Hard lighting, sometimes called harsh, specular, or sharp, will be that light which will generally cause a distinct shadow. Some hard light sources might be the sun or your electronic flash. A soft light source, also called diffuse, will create little or no shadow. An overcast sky or an electronic flash reflected into a white umbrella will give this quality of light. Many photographers enjoy working with soft light as you do not have to worry about trying to eliminate an unwanted shadow but a hard light can create drama and with practice, can be mastered.
The third property of light is quantity. How much light do we have? This property affects our exposure and film choice. If we have a large quantity of light, then we may be able to use finer grain films, smaller apertures for a greater depth of field and faster shutter speeds to stop the motion of moving subjects. As our quantity decreases, we may find ourselves having to choose a more sensitive (higher ISO) film to achieve the same result or try to use our expertise to deal with slower shutter speeds, freezing subject movement, and prevent camera shake, as well as accommodating shallower depths of field.
The fourth, and last, property of light is color. While color is generally not a factor in black and white photography, it does have an effect on color photography in two ways. The first is mood. Warm colors (reds, oranges, and yellows) will create one kind of mood while cooler (blues and greens) will create entirely another. The second way is if the light source does not match the color balance of the film. While our eyes see many different light sources as white, in reality different sources have different "color temperatures." Our brain is what adjusts them to look white, much like an auto-white balance in a camcorder. Film cannot automatically correct for proper color balance, so our pictures may have a color cast if we do not match the film being used to our light source. Most film is balanced for daylight, that is, light from the sun from roughly 10:00 a.m. to 2:00 p.m. Light's color temperature is rated on the Kelvin scale generally expressed in degrees Kelvin. Daylight is approximately 5600 degrees K. Tungsten light, i.e. table lamps, gives an orange color cast to daylight balanced film. Fluorescent light will give a green color cast. Some films come balanced for specific light sources other than daylight such as Tungsten. If you cannot find film balanced for your particular light source, then you may need to use filtration in order to correct your picture so that it looks more natural.
All of the elements will play some part in contributing to a photograph. If you find a picture you like, analyze all the elements. What light direction did the photographers choose? (it will be the opposite side of the shadow) Was the light quality hard or soft? What problems might the photographer have had with quantity of light (film choice and aperture/shutter speed considerations)? Is there an overall color cast that creates a mood? Once you recognize these elements, then go into a what if mode. What if I changed the direction or quality? Look at light in nature that intrigues you. (Be careful of doing this when you're driving.) The last and most important part is to go out and try it with your camera. Happy shooting!
Mark Smith
Mark Smith is a 1973 graduate of the Rochester Institute of Technology, New York, and teaches college level photography in the Denver area.