A photographic softbox is a device which, when attached to a light, allows the photographer to control the characteristics of that light. As the name suggests, they’re often used to imitate soft, diffused window light.
Note, a softbox itself is not a light source, but rather a tool which attaches to a light.
The interior of a softbox is typically silver or white, to help bounce the light around inside the box. Diffusion panels (sheer white) are added to the front, and, optionally, inside the softbox to help shape and soften the light.
There are a variety of shapes and sizes of softboxes available. Some are designed to work specifically with compact, Speedlight styled flashes, while others are designed to be mounted on studio continuous- and flash-heads.
Softboxes for Speedlight flashes attach in a reasonably straightforward manner, whereas there’s some more information you need to know about the compatibility of studio lights and soft boxes.
Just like camera brands have unique body-to-lens mounting systems (eg. Canon DSLRs take Canon EF and EF-S mount lenses), so do studio lights and softboxes.
Both the studio light and the softbox must have the same mount type in order to connect together.
Take a look at the front of your studio lights, whether flash or continuous, and you’ll likely see some connection points and a small release lever. As mentioned above, there are several different styles of mounting systems, so yours may well look different from those pictured here.
At the back of a softbox, you’ll find a round metal plate called a “speedring”. The speedring is the adapter which is used to connect a softbox to a light.
Again, speedrings come in specific shapes, to suit the variety of light mounts, so it’s imperative that you choose a softbox which is compatible with your light when you purchase or hire. (eg. Bowens, Elinchrom, Profoto, Broncolor, etc)
A softbox is a worthwhile investment for your studio kit if you are working with lights. Kelly often prefers to use a large (4.5 to 6 foot wide) octagonal softbox when photographing newborn, family and maternity portraits. The octagonal shape of the softbox creates lovely round catchlights in the subjects’ eyes, and the large size helps to create defined but soft shadows to add depth to dimension to the portraits.
You’ll find many different shapes and sizes, from thin rectangular strips, to small and large rectangular softboxes. Each will help shape your light in a different fashion, and should be chosen based on your requirements and vision.
TIPS FOR PURCHASING:
The speedring of the softbox needs to be compatible with the mount of your light.
Remember that some softboxes are sold without speedrings, requiring you to purchase a speedring compatible with your light, separately. Elinchrom’s Rotalux series (thumbnail link below) is an example of this style of softbox, allowing it to be used on multiple brands of lights by switching to the appropriate speedring adapter.