One of the most difficult aspects of digital photography is handling light—a task that becomes all the more complicated with the introduction of flash. Ultimately, the best light for the production of quality images is either natural light or diffused (soft) light. Light that’s not diffused, whether from sharp overhead sunlight or a light source such as a spotlight or flash, will either wash out your subject’s features or create unflattering and harsh shadows. Diffused light allows you to evenly light your subject and illuminate their features without creating harsh tones or imbalance in the image.
In the above set of images, the image on the left was taken without the aid of a diffuser. As you can see the image is overexposed, and, as a result, the subject’s features are washed out by the flash, and a lot of the detail is lost. With the flash diffuser, exemplified by the right-hand images, those details are kept intact. The difference is subtle but incredibly important, especially for portrait photography.
Types of flash diffusers
There are dozens of varieties of diffusers for flash photography. The most basic of which comes standard with most external flashes. This Neewer Speedlite comes with a built-in sliding diffuser (shown below). Most flash diffusers fall into one of two categories: opaque plastic shells customized to specific flashes, or adjustable plastic frames that can fit a number of flashes. Some people even create their own diffuser using opaque tape or tissue paper to varying degrees of success.
What if you only have a pop-up flash? No worries; there are multi-body pop-up flash diffusers that work just fine, such as the Gary Fong “Puffer”.
Many people prefer something with a bit more diffusion power than what comes standard. Fortunately, flash diffusers are among the least expensive camera accessories. The flash diffuser add-on shown on the right is a hard plastic shell that simply pops onto the external flash. This type of diffuser ranges from $2 to $25 depending on quality and manufacturer.
Unlike the hard plastic diffusers, the softer varieties can fit any number of flashes. The one shown on the left is a portable soft box (manufactured by Opteka and retails at $9.95).
Another way to diffuse light is to bounce it with a reflector or umbrella. Reflectors can often be an external flash attachment, customized to fit a specific body. By “bouncing” light, you are removing the possibility of overexposure by preventing any unnecessary light from reaching your subject.
When it comes to soft boxes and umbrellas, most people prefer having these items attached to a light stand instead of to the external flash. Although handy when you’re moving around a great deal, a pliable flash diffuser is more difficult to control than its opaque plastic counterparts.
The main difference between a soft box and an umbrella is that a soft box is often cubic in nature and fits over a flash, enclosing it within its walls, while an umbrella is open.
Umbrellas, like the one shown at right, are made of a certain material that makes them terrible for rain showers, but perfect for diffusing light. They’re incredibly versatile, giving you more creative freedom when it comes to lighting your subject.
You can use them either as a reflector to aim the flash at the umbrella, thereby increasing the volume of light that reaches the subject or as a diffuser to shoot the flash through the umbrella so that the opaque material can effectively diffuse the light.
Like most diffusers, if you don’t absolutely have to go name brand, there are a few off-brand varieties that are professional grade and relatively inexpensive.