It’s common knowledge that when photographing a person, the shape of the reflected catch light in their eye identifies the light source. It’s easy to tell an umbrella by the shape and the spokes, and a box because it looks like a window. Some photographers base their decision on which soft-light modifier to use on this, falsely believing it is the only difference. The truth is there are vast differences in the behavior of light—not only between boxes and umbrellas, but between various styles in each type.
Let’s face it—photographers are gadget freaks, equipment junkies and tinkerers. We are always looking for some other “thing” that can modify light in another way. Manufacturers are happy to comply, so we have many options to choose from. The goal is to gain control, and understand how the attachments change light.
Umbrellas are one of the easiest tools to use that provide a beautiful, soft and broad light. They come in many types: white, shoot-through, zebra, and silver. They also come with attachments or inserts such as gold or silver removable panels, and diffusion covers that both soften the highlights and warm the subject. Most umbrellas are parabolic in shape, although some have flat interiors instead of the classic bowl shape. I’ve used both shapes, and I can’t find a difference in their spread of light. I’ve found that what matters most is the quality of the white of the interior. Some are pure flat white, such as the Balcar; many others are a shiny white that almost looks silver. A lot of umbrellas are “convertible,” which means that the interior is a white diffusion material with a detachable black exterior. This creates two umbrellas in one—a white and a shoot-through. Most of these styles use shiny white interiors because of the nature of the diffusion. I, however, prefer the flat white for luminance of skin tones or a little more glow. I find the shiny white flattens out the skin, rendering it slightly gray. It goes against common sense, since you would assume the shinier the material, the more contrasty the photo. It’s a minor difference, but important to know. Umbrella sizes vary from about 30 inches to more than six feet. The most common sizes are: small, 30 to 35 inches; medium, 42 to 46 inches; and large, 60 inches. A couple of manufacturers— Balcar, Profoto and Briese— offer jumbo umbrellas or jumbo reflectors. They vary in size from five to ten feet in diameter, and use various interior materials. Some have diffusion covers as well. Umbrellas normally are mounted with the center rod under the light head. Balcar and Profoto use spring-loaded holes in the head so the light bounces into the center of the umbrellas instead of off to one side. This is a great advantage to controlling and using your light efficiently. Because the umbrella is round, the bounced light travels in a wide swath, creating a very soft light. However, the light is not even—more light reflects from the center than the edges. This makes the light fall off slowly, so the light wraps around the subject.
Umbrellas and headshots
Here’s an example: Let’s say your subject needs a headshot, so you use a standard 42-inch umbrella, positioned about 30–45o to the plane of the subject’s face and placed about three feet away. The face is mostly illuminated by the center part of the umbrella, but the edge of the umbrella closest to the front of the face (as opposed to the back of the head) provides a smaller amount of light that covers the shadow side of the face. Therefore, it’s a smooth transition from light to shadow(See Figure 1).
That edge light also automatically fills in any texture by softening the shadow. A white umbrella throws out light at about 120–140o. This translates to broad coverage of the subject as well as a lot of light falling on the background. If you use a lighter-toned background with a white umbrella, a background light may not be necessary. Because of all of these features, I believe that a standard white umbrella is the softest light source. Low contrast, soft highlights and shadows, and smooth transition to shadow give rise to flattering portraits.
Zebra and silver umbrellas
Zebra and silver umbrellas possess some but not all of the properties of the white. The light still wraps around and gives broader coverage but to a lesser degree. Silver umbrellas (which have a metallic interior and a throw of 65–100o) and zebra umbrellas (which have alternating white and silver panels and a throw of 80–110o) have unique characteristics that are crucial to understanding the quality of light. The addition of metallic material inflected by silver than white, light output is increased by almost a stop for zebra and about 1.5 stops for silver.For portraits of people with some texture in their skin, a white umbrella is the best choice. Because of the above characteristics, the color and tone of textured skin would be amplified with any metallic materials in the light source, either an umbrella or a box.
The light box (commonly called “soft box”) is a rectangular box that mounts on a light head with the head pointed straight to the front. The interior is usually white, with an inner diffusion panel and a front diffusion panel. The light bounces around the white interior, is diffused by the inner baffle, bounces around again, and is diffused again when passing through the front panel. All this bouncing and diffusing creates very soft light. Box have very different properties than umbrellas. Light emanating from a box is even from top to bottom, side to side, center to edge. Larger boxes may have a minor fall off at the edge. This translates to soft and even light rather than the wrap-around of an umbrella. any light source accentuates the following:
• Detail. Light bounced off metal is able to penetrate the surface of the subject and bring out more detail and texture. If the subject is fur, feathers, hair, solid color fabric where showing the weave is important, a zebra or silver umbrella works much better than white.
• Color saturation. The intensity of metal causes richer, brighter and intense color.
• Contrast. Because of the higher reflective nature of silver, highlights are hotter.
• Directional light. Light reflects at a tighter angle, so the coverage is smaller with less light falling on the background or the fill card.
• Higher f-stop. Since more light is reflected by silver than white, light out- put is increased by almost a stop for zebra and about 1.5 stops for silver. For portraits of people with some texture in their skin, a white umbrella is the best choice. Because of the above characteristics, the color and tone of textured skin would be amplified with any metallic materials in the light source, either an umbrella or a box.
The light box (commonly called “soft box”) is a rectangular box that mounts on a light head with the head pointed straight to the front. The interior is usually white, with an inner diffusion panel and a front diffusion panel. The light bounces around the white interior, is diffused by the inner baffle, bounces around again, and is diffused again when passing through the front panel. All this bouncing and diffusing creates very soft light. Box have very different properties than umbrellas. Light emanating from a box is even from top to bottom, side to side, center to edge. Larger boxes may have a minor fall off at the edge. This translates to soft and even light rather than the wrap-around of an umbrella. The throw of the light is very small, about 50o. Wherever light falls on the subject, the f-stop reading is the same, but shadows happen quickly, and little light falls on the background. It’s similar to a window, which is what it’s based on. The diffusion material warms the light since some of the weaker, bluer wavelengths are blocked. Boxes come in a variety of sizes: 16x 22 inches to 54×72 inches, and also strip lights from 9×36 inches to 21×84 inches, and some specialty ones like the Chimera 10×30-foot box, which is used to light cars. Several manufacturers offer a choice of white or silver interiors. The silver interior provides all of the characteristics in the list above. Photoflex makes a series of boxes that come with a white interior and velcroed panels in gold and silver. You can add one gold panel for a little warmth, two for more, or all four for a tungsten look. Adding silver provides all the contrast and color saturation without the warmth. Silver is good for lighting black or textured products. I’ve used boxes for most of my product work, and silver boxes to photograph camera gear and furniture.
Size matters, and distance, too
There is a very simple rule: The size of the light source should be proportional to the size of the subject. The distance of the light source to the subject should be similar. For example: a head-and- shoulders portrait from a little above the head to slightly above the waist is about 30 inches. You want a slightly larger umbrella so that most of the subject has even coverage with no fall-off at the top of the head, so a “standard” umbrella of around 42 inches is perfect. If you used a 16×22-inch box, only the head would be illuminated. Remember that the height of the light head should be above eye level so you are using the center part of the umbrella. If you had the head lower than eye level, then most of the light from the umbrella would be under the person’s face, creating “monster light.” The same is true of a box.
Light-source size is very important to get the kind of coverage you need. Of course, the purpose of the photo determine that size. I’ve lit full-length people with a standard 42-inch umbrella. With the broad spread of light, the feet may only lose about one stop, which is very little visually. For shots of clothes or a bridal portrait, broader coverage is necessary, probably a 60-inch umbrella or a large 54×72-inch soft box. The larger the light source, the softer the light because the light comes from everywhere. I use umbrellas to light couples and groups because of the wide throw. In fact, I use a standard umbrella for groups up to six people.
Here’s an exercise to help you understand. Hold your hand with fingers out- stretched with your palm towards your face about four inches away. If your hand is the light source, you can see that your face would be broadly lit. Now hold your had arm’s length away. Same light source, same size but the distance effectively reduces the size compared to the subject. Using a light too far away changes the quality by making it harsher. The opposite is true as well. When lighting small objects, a smaller light source is necessary. Lighting a pear with a 42-inch umbrella would flood the light everywhere. Using a small spotlight would be better. Balcar makes micro lights, which are fiber-optic cable that attach to the head with three cables extending. I’ve used them for toys and other small products.
Both umbrellas and boxes create soft light. Is one softer that the other? Actually, no. Look at the close-up comparison and notice that where the light hit the subject fully, the quality is pretty much the same except for the warmth from the box. But the properties of the lights are different: umbrellas have wrap around and gradual fall off with broad coverage and spread, boxes are even with quick fall off, more directional and little spread.
One last word about catch lights. Some manufacturers make oval covers for the front of the box, creating a round (instead of square) catch light. Some even have a white interior covering the umbrella ribs so there’s no “spokes” in the catch light. I worked on a product shoot for a camera manufac- turer for which we created our own covers in various shapes to reflect in the lenses. I even had a student create a heart-shaped cover! The truth is, who cares? The quality of the photo is what’s important, with the lighting matching the concept for the subject.