Choosing the Right Softbox: Does Shape Matter?

The softbox is arguably the most critical component of your lighting kit, whether you are capturing headshots or lighting a video interview. As with most lighting tools, no single softbox is perfect for every scenario. Grasping how different shapes function will help you select the right tool for your specific creative vision.

To simplify the selection process, we can categorize softboxes into three primary shapes: the classic rectangle, the rounded "octabox," and the tall, slender "stripbox."

Rectangular Softbox: The Classic Shape

If you are purchasing your first modifier, the 3'x2' rectangular softbox is an excellent starting point. While size varies, the primary reason to choose a rectangle is its shape.

Its flat sides allow it to be placed flush against a wall, a technique often used in small studios. The straight edges also offer superior control when "feathering" light, especially when the modifier is positioned just out of frame. A rectangular softbox aligns perfectly with the edges of your camera frame, maximizing coverage without intruding into the shot.

These advantages also apply to square softboxes, but the rectangle wins on versatility due to its ability to rotate. You can turn it horizontally to wrap light around a subject, or spin it vertically to use it as a clean white background for portraits.

Some photographers avoid rectangular softboxes for headshots because they create square, "unnatural" catchlights in the eyes. While this is a valid concern for key lights placed directly in front of a subject, it is irrelevant when the softbox is used as a side light or backlight.

Octabox: The Round Option

Despite the name, an "octabox" isn't always eight-sided; they can range from six to sixteen sides. The core concept remains the same: more sides create a rounder, sturdier shape.

The primary benefit of this roundness is the catchlight it creates in a subject's eyes. Unlike the square reflection of a rectangular box, an octabox produces a round reflection that mimics the sun, which many find more natural. The more sides an octabox has, the circular the catchlight appears.

One common misconception concerns the "Deep Octabox." These are often marketed as having the ability to focus light into a tighter beam due to their parabolic shape. In reality, the front diffusion fabric scatters light in all directions regardless of the depth of the box. While the light may be more even, it is not necessarily more directional.

Stripbox: A Specialized Variant

Technically a variation of the rectangle, the stripbox has distinct properties that warrant its own category. It is important to note that despite the name, a stripbox does not project a focused beam or "strip" of light; the outer diffuser still spreads light in all directions.

The stripbox is defined by its dimensions. A 1'x3' version is perfect for small home studios, offering the length of a larger modifier without the width. Longer versions, such as a 12"x56", act like two modifiers in one: a large, soft source in one orientation, and a narrow source with rapid light falloff in the other.

You will most often see stripboxes used as rim lights (or "kickers") placed behind and to the side of a subject to create separation from the background. They are also excellent for lighting hair when boom-mounted above. However, they can also be used as a creative key light; rotating a stripbox from vertical to horizontal can dramatically change the mood of a portrait.

Conclusion

There is a vast array of softbox shapes available, each offering a unique aesthetic. You might require the specific control of a large stripbox, the robust roundness of a 16-sided octabox, or perhaps just a reliable workhorse like the classic rectangular softbox. Understanding these differences ensures you get the best value and the best results for your photography.