Hard light casts dark shadows with sharp edges while soft light, if extreme, can eliminate the shadows entirely. Hardness and softness of light are determined by the size of the light source and its distance from what it is you’re photographing. So, the sun is a source of hard light because it is really a small diskand it’s very far away. The farther away the light source and/or the smaller the light source (in relation to the observer–i.e. the sun is small), the harder the light. For a quick comparison, think of the difference between northern light and light with the sun shining through the window, southern light. If you place your subject next to a window that’s lit from the north, it will be lit very softly such that you’ll barely see a shadow. As you move in and away from the window, the light source (the window) becomes smaller relative to the subject and starts to cast harder shadows. When placing your subject in direct sunlight, it doesn’t matter how far you are in the room since the hardness won’t change with increasing distance from the sun. (The sun is so far away that small variations in distance form the source make no difference.) The sun will cast strong, dark shadows. Now we must think of how to control these two kinds of light. The most natural setup—outdoors—allows us to use both hard light (coming from the sun) and soft light (coming from the sky). The sky “fills” the shadows by casting soft light all around the set and softens the effect. Sometimes, however, this natural filling of shadows with sky light, is insufficient—the shadows remain too hard. In this situation there are a couple of options. The sunlight can be shone through a scrim—a sheet of cloth or other material that partially blocks and breaks up light—which spreads out the light source and softens it. Or, the shadows can be filled directly by adding an additional light source (if using hot lights or flash) or by simply placing a fill card—a piece of white foamcore—next to the subject, right next to the shadow. The foamcore reflects light back into the shadow and makes it less dark relative to the rest of the subject. You may wonder why it is necessary to control the hardness of light so carefully. The problem has to do with the way cameras “see.” Our eyes have apertures (pupils) that are constantly adapting to varying amounts of light, closing down when looking at bright objects or opening up when looking at a shadow. Since cameras don’t have this ability to constantly adjust to the amount of light, they may render objects too light or too dark. Shadows may become so dark that they contain no detail; high lights “blow out” and contain no detail—the range of brightness on the set is too much for the camera to handle. In landscape photography, there isn’t much a photographer can do to control the contrast in the photograph. He or she may use a neutral density filter to subdue a sky, but in general the options available to the photographer are very limited—unless the photographer is shooting black and white and using the zone system (more about this in a subsequent entry). In still life photography, however, there’s much we can do to control the contrast on the set and the relationship between hard and soft light. Let’s assume we’re using natural, available light and that we have a beam of sunlight shining in through the window. If we place an object in this beam, it’s going to cast a very hard shadow (some of the hardness will depend on whether the studio is black or white since the studio itself acts as a fill light), making it difficult to fit both the bright parts of the image and the shadow in the same photograph (see below, contrast). We can control the light source and make it larger and dimmer by using some kind of scrim material. We can also “fill” the shadow(s) with a white fill card.

Hard light and soft light also create different kinds of reflections. A very hard light—a very small light source—will create what’s called a specular highlight. A specular highlight is a tiny spot of light, very bright, that makes the picture look harsh. The reflection of this highlight will also be very bright such that it will never show detail in the shot. Soft light, on the other hand, creates large soft reflections and soft shadows that help model the object being photographed. The choice to shoot in hard light or soft light is one of personal preference. (I shoot in hard light whenever the sun moves around in my studio.) Hard light raking across a bunch of carrots, for example, will bring out a lot of crisp detail. Hard light can be controlled by placing small objects in its way to block the beam in very specific places—places that would otherwise blow out. Soft light is much harder to control because it’s more diffuse.