Light Shaping Tools

by Garry Edwards

I hope that my first article on How to Choose Studio Lighting is helpful. The choice of which lighting system to use, although important, is just the very start of your journey towards good lighting. The next step is to understand the importance of the light shaping tools (or modifiers) that fit onto the light itself and shape and control the light. It’s the light shaping tools and the way that you use them that really matter.

Some Example Light Shaping Tools

This article deals with the light shaping tools that are used with studio flash heads—flash is my equipment of choice. The principles laid out here apply to all types of lighting including hotshoe flashes and continuous lighting, even though the tools available for these types of lighting are far more limited in both their scope and effectiveness. Basically, there are only two different types of modifiers—those that make the light bigger and those that make the light smaller. Bigger lights produce softer lighting, smaller ones create harder lighting.

First Forays into Light Modifiers

Generally, the very first light modifiers that beginners buy are those that make the light bigger, so we’ll start with those.

Reflective Umbrella

The simplest (and cheapest) is probably the umbrella. This is a reflective umbrella, the light from the flash bounces into it and then bounces back on to the subject. Reflective umbrellas come in various “flavors”—some have white interiors, some silver, some gold and there are even some with Zebra stripes of alternating white and silver. White umbrellas produce the softest light and silver ones produce a harder, more specular light. The striped ones produce a combination of white and silver, and gold umbrellas produce a quality of light similar to the silver ones but with a ‘warmer’ tone that produces an instant fake suntan. This can be useful when combined with light from white sources, and especially when used as a hair light, which we’ll get to later.

The advantage of reflective umbrellas is that the light is reasonably well controlled and doesn’t bounce around everywhere. The disadvantage is that the design forces the flash head to be between the subject and the umbrella, which means that it can’t be placed close to the subject so it can’t produce very soft light.

We get soft light by using a large light (the reflective surface of the umbrella becomes the light source) but size is relative, and even a large light source becomes small, in relative terms, if it isn’t close to the subject. Getting it closer to the subject makes it bigger in relative terms, so the light becomes softer.

Shoot-through Umbrella

If we want softer light from an umbrella, we need the shoot through type, which can be placed as close as we like to the subject.

Not that shoot through umbrellas are perfect either, because generally only about 60% of the light actually passes through it, the rest bounces back and, in a small studio, will bounce off of the ceiling, walls, etc. This creates pretty uncontrolled lighting and if the light also bounces towards your camera lens it can cause flare too.

And then there are the combination umbrellas, they have a black back which is removable. With the back in place, they are reflective umbrellas, and with the back removed they become shoot through umbrellas.

Umbrellas are cheap, they’re effective with all types of flash and they are the only really effective soft lighting accessory when used with hotshoe flashes so it’s not surprising that they’re very popular.

But the problems of unwanted light spill, especially when used in small rooms, can lead to disappointing results, so it’s not surprising that people try to avoid these problems by using a softbox, which combines the benefits of both reflective and shoot through umbrellas.

Softboxes

Softboxes come in all sorts of shapes and sizes but most of them work in the same way—the softbox replaces the reflector that would normally be fitted to the flash head, the light spreads around inside the softbox, bouncing off the walls and then hits an inner diffuser, a sheet of white translucent plastic, which evens out and diffuses the light. Then, in front of this inner diffuser is the front diffuser, which you can see in the picture. This diffuses the light even more. The walls of the softbox are typically a stippled silver material. Silver is highly efficient and the stippled surface helps to break up the light and spread it evenly. A few softboxes, including my Chimera, are also available with plain white interior walls. Plain white is slightly less efficient than silver (about 1/5th of a stop) and produces slightly softer light.

As you can see, the whole of the front diffuser becomes the light source so, if it’s close enough to the subject it can produce soft lighting with gentle shadows, and because the back of the softbox is enclosed there is no stray light bouncing around from the back.

Softboxes are simple pieces of kit but the differences in their design (and build quality) can be surprising.

The ideal softbox is one that allows the light from the flash head to bounce around and get thoroughly mixed up before it strikes the inner diffuser. Some of the better makes have an extra layer of diffusion (actually more of a central patch that partly reflects the light) to prevent hotspots and bounce some of the light from the center of the light back towards the light once more.

And what happens to the light once it reaches the inner diffuser? Well, in an ideal world all of the light should be forced to pass through the diffuser on its way to the outer diffuser, but some of the less well-designed models have a fairly large gap between the inner diffuser and the walls of the softbox, which allows some of the light to bypass the diffuser. The front diffuser is important too. The better ones tend to be thicker and denser than most. They still produce soft light but the light is crisper, better defined.

Some of the better-designed softboxes have a recessed front diffuser with a pronounced lip protruding from it, which helps to prevent unwanted light from traveling back towards the camera lens and causing flare. This lip also makes it easier to “feather” the light, i.e. to light the subject (or background) to create a graduated effect.

In theory, softboxes can be used with any type of flash but only lights that have removable reflectors can work really well, because with a fixed reflector in place the light tends to aim directly at the inner diffuser without first bouncing off of the softbox walls. A few hotshoe flashes are fitted with removable reflectors. Most are not, which makes them less than ideal. Softboxes can also be used with some kinds of continuous lighting too, although low power output and heat can be a very real limitation when using continuous lighting.

People argue endlessly about the “right” size or the “ideal” shape of softboxes but it’s really down to horses for courses when it comes to size and shape. Typically, if I was photographing a wine bottle I’d use a narrow rectangular (striplight) softbox to produce the shape of specular reflection (reflection of the light source) that suits the subject, and even though wine bottles are pretty small I’d use a 6’ high softbox so I could choose how large that specular reflection could be and how far away the softbox could be placed. Small softboxes often can’t be placed close enough to the subject to produce the effect needed.

If I was photographing a person full length [example below—links to larger image], I might choose a large rectangular softbox for the key light. For a headshot, perhaps a square or octagonal softbox, depending on the shape of catchlight that I wanted the eyes to show.

As you can see from the eyes of this portrait below [click on image to see a larger version], a square softbox can produce natural looking highlights in the shape of a window: “glazing bars” can easily be added by attaching black tape to the outer diffuser if required. The softbox was positioned in a fairly classic position—above and to one side where it produced lighting that is soft but without being flat.

Sometimes you may want a small softbox, especially if you’re shooting in a small room, because a small softbox will allow you to produce controlled, diffused light without it being soft. In a large room, a similar effect can be produced simply by moving a larger softbox further back.

One size and one shape of softbox cannot meet all needs. You really need several—but if budget and/or space is a problem, and you’re limited to just one softbox it’s generally better to get a large one and to be able to change the size and/or shape. Some softbox manufacturers supply removable masks that change the effective shape from square to octagonal. A more versatile (and cheaper) solution is simply to mask the front diffuser of your softbox to produce the size and shape you want, simply by temporarily fitting your own mask. The standard method is to fit blackwrap (Cinefoil) using clothes pins, but black trash bags will work too.

A lot of people mistakenly believe that the sole function of a softbox is to produce soft light—softboxes can do far more. In the “Black is Beautiful” [image below], I used two softboxes. They were both behind and to the side of my subject so that they lit the edge of her body and spilled some of the light across her back. The one on the right was higher because although I didn’t want to light the back of her head I did want to light her face. The important thing here was to get the lighting level the same on each side and to arrange both softboxes so that the light skimmed across my model’s back. Used in this way, softboxes can combine soft overall lighting with fairly hard local lighting or to produce low overall contrast and high local contrast.

There are other ways of getting soft light too. Any type of flash can be bounced from a white ceiling or a wall, which turns the ceiling or wall into the light source. There are also artificial tools such as lighting silks (basically just a diffusing material such as ripstop nylon or plain white shower curtain) that can be used instead of a softbox or umbrella or used in front of one to increase the size of the light source or to diffuse the light more.

Unwanted Light Spill From Large Light Sources

Soft lighting normally involves using large, diffused light sources such as softboxes, shoot through umbrellas or scrims and this can cause its own problems. Softboxes are the most efficient large light sources (because all the light is traveling in just one direction, or at least in theory) but of course it doesn’t just get to the subject and then stop—it goes past the subject and bounces off the background, it spreads out and bounces from the walls and ceiling too. In fact, there’s a great deal of ‘bounce’—at a distance of 12’, a 3’ x 3’ softbox creates a “beam” of light 25’ high and 25’ wide.

So what happens to that bounced light?

Bounced light goes everywhere, or at least it does in a small studio. For beginners who are just trying to get very soft lighting, this may seem to be an advantage of sorts—but once you’ve moved past the soft lighting stage, you’ll want to control your lights—and you’ll feel frustrated that whatever you do you’ll find that bounced light has lowered the contrast, caused lens flare and stopped you from creating the shadows that are needed to shape faces and add interest.

What can you do about it?

Well, some people think that the answer is to put a honeycomb (grid) over the front of the softbox. These honeycomb grids are expensive and you may want to think carefully before you spend your money.

What the honeycomb grid will do is to control the spread of light. If you get a fine one with a 20 degree angle then the spread of light from our 3’ x 3’ softbox at 12’ will reduce from 25’ to 8’—but it will also lose its wrap around qualities, the shadows will be much harsher and it will give an effect much more similar to a beauty dish than to a softbox. It will also “lose” around 4 stops of lights so, for example, your 300 Joule flash head will only produce the equivalent of 16 Joules.

There are really just 4 possible answers that work.

Use a large studio. If you have a high ceiling and if the walls are distant, bounced light won’t be a problem. This “solution” isn’t practical for many people.
Paint the walls and ceiling black. White paint is the worst possible studio decoration because of the “light bounce” problem. Black is the best. Studios with black walls and ceilings are depressing places to work in and it isn’t a practical solution if your studio has to double as your living room.
Paint the ceiling black and have black drapes that can be pulled across the white walls when required. This is probably the ideal solution for high street portrait studios that need to look cheerful but also need to work efficiently. It isn’t practical if your studio is also your living room.
Make do with what you’ve got but gain control of bounced light by using flags. Flags are simply pieces of black painted card or board, or better still Cinefoil. Place flags wherever they need to go to stop light bouncing around and ruining your shots. The look untidy and it takes time and a bit of thought, but it’s the only way of controlling light spill in a small space with light colored decoration. And it’s cheap!

I mentioned shoot-through umbrellas and silks. The light spill from these is far worse than with softboxes and although you can use flags in exactly the same way, it’s a bit more difficult to control all of the light spill.

Final point about achieving soft lighting

This leads me to my final point about limiting light bounce and getting soft lighting. The light needs to be close or it won’t be soft. It needs to be so close that it will be physically in your way. Work around that, but don’t move the light further away to make your life easier, unless your softbox is producing lighting that’s softer than you want it to be at the present distance.

By having your softbox really close, the effect of the bounced light will be reduced. The reason for this is that the further the light has to travel, the more power it loses. If the light that reaches your subject only has 3’ to travel and the light that bounces off the nearest wall has 6’ to travel, a lot of the power of the bounced light will be lost in traveling 6’ to the wall and another 6’ back again. Some of the light will be lost in reflection too. Probably no more than about 70% will actually reflect from any surface except a mirror.

To summarize, softboxes and other large lights sources will produce soft lighting if they are fairly frontal and very close to the subject. If they are moved farther away, the light becomes progressively less soft because the light becomes smaller in relation to the size of the subject and the light can no longer produce the wraparound effect needed for really soft lighting.

As a general rule of thumb, softboxes have really lost most of their ‘soft’ qualities once they’ve been moved further away than the measurement of their diagonal. As an example, a medium softbox, 4’ x 3’, has a diagonal measurement of 5’ and so needs to be used no further away than 5’ if soft lighting is wanted. To get really soft lighting it needs to be placed much closer than that.

Concerning Reflectors

Reflector

Before we move on, I want to mention reflectors—not the type of reflector that fits to the flash head. The type I’m concerned with here are the reflectors used to reflect light on to the subject.

Almost any type of material can be used as long as it’s color neutral: foamboard, white card and white foam insulation sheets all produce good results at a very low cost. Then there are the purpose-designed reflectors such as the one in the image to the right, which is one of those spring-open gizmos that can be twisted back to 1/4 their original size and put back in their bag, assuming of course that you have strong wrists and a degree in physics.

Reflectors are placed to “catch” light that has passed by the subject, and the light is then reflected back onto the subject to reduce shadow intensity. It’s a simple yet brilliant concept because it’s convenient, cheap and effective. A reflector can never produce anywhere near as much intensity of light as the light it reflects. This is simply because light loses its power over distance. The light reflected from our reflector has to travel further to the reflector than to the subject and then has to bounce back again, increasing the distance. Also, the reflector absorbs some of the light anyway reducing the efficiency even more. Generally, we want fill light to be much weaker than the main light anyway, so that’s not a problem.

5-in-1 Reflector

The reflector shown here is silver, which is highly efficient but produces specular light. Reflectors are also available in plain white, gold (to produce a “warm” look) and various other choices including black. Black ones aren’t technically light reflectors at all, they’re light absorbers and are normally placed to create a dark edge or a dark area on the subject. Plain white ones can also be used as a bounce surface to produce soft light in much the same way as a wall or ceiling.

Reflectors are also available in sets, like the one pictured here. This is a 5-in-1 set and includes white, silver, gold and black surfaces. That only adds up to four variations, number five is a diffuser, used to further diffuse light, useful both in the studio and when shooting outside in bright sunlight.

Let’s move on to Beauty Dishes

The picture [below left] is of the Lencarta Beauty dish, which is available in 70cm and 40cm sizes. Other manufacturers, Bowens and Elinchrom for example, offer different sizes. There doesn’t seem to be a standard size. Beauty dishes are just large reflectors that channel the light in a controlled way. They have a deflector in front of the flash tube to prevent hotspots and they produce a reasonably soft light but the light is less soft than that of a softbox or umbrella of the same size set at the same distance.

Note the lip at the front, which is for a honeycomb grid available for most brands.

The picture [below middle] is another beauty dish with a honeycomb grid fitted. The honeycomb grid concentrates the light into a smaller area, makes the light harder and can also prevent flare when used as a backlight or a hair light, because the spread of the light is restricted. Most Beauty Dishes can be supplied with a diffuser, or shower cap too.

Used with a diffuser but without a honeycomb grid, the Beauty Dish can supply a very similar quality of light to a perfectly round softbox. Bowens [below right] offers a diffuser that has a removable honeycomb grid in the center.

Let’s move on to some examples with just a single light.

There is no such thing as a “correct” lighting tool, just the right one for a particular job. Usually I end up combining light from different lighting tools in the same shot to get the effect I want. However, that’s a topic for future articles.

The following is a fairly classical Beauty Dish shot.

When I’m using softboxes as the only light, I usually find that the softbox needs to go at more or less a 45-degree angle above and a 45-degree angle to one side. That doesn’t work with Beauty Dishes. I find that the best place is normally still fairly high (often very high), but pretty much in line with the face—if the model is looking straight at me then the beauty dish is normally straight above my own head. If she’s looking off to the right as the example image above, then the beauty dish is off to the right too in line with her face.

The image below is another example, again with the beauty dish in line with my model. This was shot without a diffuser fitted and the light is pretty harsh, which I feel suits the subject well. This type of lighting does tend to show up any skin defects and because of this some retouching is normally needed. As always, the catchlights in the eyes give a very good indication of the type and position of the light and, as you can see here, the beauty dish was directly above the camera but very slightly to the right, to create some shadows.

Newcomers to lighting often seem to believe that shadows should be avoided. In fact the reverse is true because shadowless lighting will make any face look flat and uninteresting. The trick is to control the shadows so that they work for us, not against us. Let’s analyze this shot to make sense of that statement.

Placing the light above eye level does two things: the most obvious is that it places the catchlight fairly high in the eyes, making the eyes look bigger. At least as important but less obvious perhaps, it creates shadows that define the shape of the face and show its qualities. Because the light is fairly soft, the shadow’s transfer edges are soft and gentle too, but they’re clearly visible.

Note the shadow of the hair on her forehead and neck, which makes the shot 3-dimensional, and the sideways shadow from her nose, which does the same job.
And note how the light falls off in intensity as it travels down her face. This is caused by having the light close to the subject (remember that any point source of radiated energy, including light, loses its power to the square of the distance traveled.)
See how the top of the cheekbones are creating shadows of their own, which emphasizes the high cheekbones.
Can you see the gentle shadows under her nose and lower lip, which add to the 3-dimensional effect?
Can you also see the much harsher shadow under the chin, which separates the face from the body and draw your attention to it?

There’s a tradeoff of course. This type of lighting also reveals skin imperfections and casts unwanted shadows under the eyes, making a degree of retouching essential. Putting the light in the position in which it emphasizes the model’s beauty only works when I want the model to actually look beautiful. In the shot below I wanted that fairly hard lighting to show her looking vulnerable and frightened, desperate to escape from a cage.

Retouching a shot like this is difficult because of the problems caused by the bars in the shot, so the lighting needs to be right at the time of the shot. That applies to every shot because light is three-dimensional. Fakery on a two-dimensional computer monitor is no substitute for the real thing.

Please compare these two shots of the same model, wearing the same clothes, side by side.

The lighting is identical in the two images, but as you can see it produces a very different effect—in the shot above left she is looking directly at the light, which I hope makes her look seductive and attractive, and in the shot on the right she is looking straight ahead. The light is making her look stressed and vulnerable and is casting the shadows of her cage on her face and body.

Conclusion

I’ve concentrated on “soft light” tools in this article such as reflective umbrellas, softboxes, reflectors, and Beauty Dishes. Keep in mind that any lighting modifiers that aren’t placed close to the subject can also produce “hard light”. The next article in this series will feature “hard light” tools such as honeycomb grids, fresnel spotlights and focusing spotlights.

Photography is art ?

Thursday, January 6, 2011