Mainlights & What They Do

Mainlights & What They Do

by William Lulow

Mainlights provide the basic, overall illumination for a photograph. They are usually directional so the light they create is aimed at the subject. They provide most of the information in a photograph.

The Photographic Umbrella

The light I use most for portraits in the studio is my custom-made, large photographic umbrella. When I describe how light behaves when photographing a human being, it’s important to note the characteristics of this lighting tool:

1. It is large
2. It is round
3. Light is spread over a large area
4. Light even tends to wrap around the subject especially when flash is used, because of the nature of flash lighting generally.

Many people have seen photographic umbrellas, but just as many don’t really know why they are used. Mine is approximately five feet in diameter! That’s a large mainlight.

In a previous article, I referred to a small, on-camera flash as a “point light source.”  Here is such a light:

Typically, the actual flash tube is a small, rectangular light which is aimed directly at a subject, usually from the position of the camera because it would be mounted on the camera’s hot shoe.

It creates harsh shadows and very specular light. This type of light is not conducive to producing soft, wrap-around type lighting effects. One of the reasons for this is that lights that are built in to cameras or are designed to sit on top of them, are quite small when compared to almost anything they are used to photograph. Therefore, photographers for many years have searched for ways to make their lights bigger. They used theatrical Klieg lights and otherwise manufactured large lights because they knew that that’s the way to get soft lighting effects. Finally, they turned to using photographic umbrellas to get the soft effects they were after because they could be folded down and stored so much more easily.

Now I have used and seen how various mainlights behave under a wide variety of uses and I have seen the effects of large lights on various subjects over my more than 40 years of doing studio photography and the rule that has emerged is that the larger the light source in relation to the subject, the softer the lighting effect will be. That is assuming you are looking for a soft light to begin with. Most commercially usable images of either a person, a group of people or products really need a soft light that has very few shadows or where the shadows are transparent. We need to be able to see people’s features as well as those on even small products.

Umbrellas work well because they do several things at once:

• It makes the light source much bigger than on-camera flash
• It softens the effect of the light because it has to travel at least twice the distance to the subject (flash heads are “bounced” into the umbrella)
• The light itself, is quite large compared to the size of a human face
• Umbrellas fold up to an easily transportable size

If you look at my studio umbrella above, you will notice that its shape is quite round. It means that the light bounced off of it will follow a round pattern and essentially “wrap around” the subject. So it’s the size and the shape of it that creates the softness quality of the light that is reflected from it. Also, using an umbrella also means that the light source is not attached to the camera.  This creates different effects because the light can be placed at various positions, not on the same axis as the camera.

This photographic umbrella has a satin inside and a black outside. The black part keeps the light focused on the subject. Some photographic umbrellas are made from a translucent material that lets light through it. This actually defeats the purpose of the umbrella. These umbrellas can be used as a “diffusers” to spread the light over a slightly larger area, but they don’t actually make the light any bigger because light really doesn’t “bounce” off of it and as a light source, it is really just about the same size as the light inside it.

The whole idea of a large photographic umbrella is to make the light source itself as large as possible. An additional fact is that many umbrellas have only six to eight ribs that hold the fabric. If there are only six ribs, the umbrella fabric will contain straight lines at the ends of the ribs. This makes not only for ugly looking “catch lights” in subjects’ eyes, but it cuts down on the wrap-around pattern that is created. So, I had an umbrella made with sixteen ribs and was able to create a round light source as mentioned above.

I normally don’t take this umbrella with me on location unless I am setting up my studio-type lighting in an office or home. Here’s a shot of me actually using it to photograph my oldest granddaughter:

The Softbox

Over the years, photographers realized that in order to make the output of a light as soft as possible for effective lighting of people, the light had to be very large compared to the size of a person and it had to be bounced or diffused somehow. I worked with several photographers when I was beginning my career as a studio photographer, who used very large light banks when they photographed models for fashion catalogs like JC Penney, for example. Some of these lights looked like this:

These were “softboxes” that were often more than six feet high and roughly four feet wide. They were designed to be about the size of a normal human being. They provided an even, soft light because the light “head” (or heads) placed inside it was diffused by the white, translucent material in the front of the box and aimed by the black material surrounding it. This was a fairly effective means of creating a nice, soft lighting. But, they were often cumbersome and not that easy to use. In fact, one photographer I worked with had a really large softbox into which he placed about eight flash heads, each one attached to a flash generator or “power pack,” which it was my job to watch. I had to make sure that each of the flash heads fired for each exposure. If one did not fire properly, the exposure would be diminished just enough to underexpose the entire piece of film, thus rendering the picture the tiniest bit too dark. So, this piece of lighting equipment, although correct in its usage, was really difficult to operate, especially for a single photographer who had no one around to help keep an eye on this stuff.

As you can see, these softboxes do provide some soft light. But because they are rectangular in shape, instead of providing a round, wrap-around type of light, they are able to AIM the soft light toward the subject more effectively than umbrellas can. Again, I have discovered after decades of using both these and umbrellas, that softboxes are much better for lighting objects. Their light output is a bit more intense and the reflections they create are much more suitable for objects of similar shape, such as boxes. Here is an example:

Notice the rectangular hightlight which provides the defining light on this tea kettle. It is a soft light, but one that has definite direction to it. Here is another example. Note the highlights and how they help to make the objects look longer:

Good and effective mainlights should be designed to soften the effect of the light and should have a black backing and a satin interior so as to direct the light forward. And, as I have noted, they need to be as large as possible to obtain truly soft results. When a photographer does a portrait and uses a “main light,” (the light that provides the basic lighting for a portrait), that light is always reflected in a person’s eyes. The reflection is called a “catchlight.” If this reflection is distracting because it’s the wrong shape or a funny shape, like a ringlight, it detracts from the overall quality of the picture. It will always be noticeable because it will reproduce as bright white. In any picture, things that are white tend to jump out at us as viewers and things that are dark will recede and not be as noticeable.

The other big difference between using a large umbrella and a large softbox is that the former provides a kind of “wrap around” lighting effect due to the curved nature of the umbrella. The softbox is only a means of directing soft light where you want it. The light rays from the softbox tend to be directional in nature and not create light that goes all around the subject.

Here is another example of a portrait made with my large umbrella:

This is a recent portrait shot with my large, soft umbrella. You can see the catchlights in her eyes. The top one is the umbrella and the smaller one is a lightbox which I use as a fill-in light to lighten the very slight shadows created by the umbrella. I am always looking for definition in skin tone, but without any really distinct shadows. Notice how soft the overall effect is and how translucent the skin tone is. That is the effect I’m looking for in just about all my portraits of women. Now, without the addition of any fill-in light, the light is still soft, but with a few shadows. Here is an example:

Here, you can notice that the picture has no fill-in light. Therefore, the neck is darker and there is a very slight shadow under the nose. But the overall effect of the light is still soft and even. Men can usually take a lighting without a fill-in, because their skin is harsher with more wrinkles. Those qualities make men look more masculine but wouldn’t be as flattering for women.

The take-away for this article is that the mainlight sets the tone of the picture.  It will provide very soft light, if it is large enough, but you have to have the room in which to use it and you need to know how it works to provide round, soft, large light for your portraits. The softbox will also provide soft light, but it will be directed much more than that from the umbrella. These are the two, major light sources photographers use. You have to know what each light does and how to use each one.