Some time ago, I ended up in a discussion that got me thinking. You're probably aware that the softness of light is affected by the size of the light source and the distance between the subject and the light source. But what happens if I use a shoot-through umbrella aimed at the subject and compare that with an umbrella turned away from the subject, bouncing the light?
It struck me that with a shoot-through umbrella, the convex shape means a smaller part of the umbrella surface actually lights the model. The rest of the light illuminates the surroundings. When the umbrella is turned away from the model, the reflective properties may result in similar or even softer light than a shoot-through umbrella of the same size.
Instead of guessing, I had to test my theory. To begin, I placed a shoot-through umbrella as close to the model as possible without interfering with the composition.Then I rotated the flash/umbrella while keeping the stand in the same spot, maintaining the angle toward the model in both shots.
I used the same transparent umbrella for both test shots. This means light will bounce differently in the studio depending on how the umbrella is used, but it’s a large space and we’re interested in the gradient between light and shadow. We'll ignore any fill effect. Since the flash is very close to the model, reflections in the studio don’t affect the result significantly. Had I used a reflective white umbrella, we would have had more light on the model (= different exposure), but the softness would have been the same.
So... the first test was a lighting setup where I let the flash pass through the umbrella fabric, placing it as close to the model as possible. I aimed the light so that the umbrella’s central rod pointed just in front of the model’s nose, creating the softest possible transition from light to shadow.
Below is a sketch. The blue line in the umbrella indicates the approximate area actually lighting the model. The rest of the light spreads around the studio, lighting both photographer and background.
I carefully measured the light with a meter placed right at the bridge of the nose to ensure the same light output for test #2. Also, make sure the flash head lights up the entire umbrella. Why use a large umbrella if you don’t fill it with light? Turn on the modeling light and see how the light spreads. Pull the umbrella out a bit to spread the light or push it in to avoid spill from the sides.
For the second test, the flash stand remained in exactly the same spot. If the light is as soft or softer from this position, there’s room to move the light even closer and create even softer light. When the flash reflects inside an umbrella and the concave side faces the model, the entire umbrella surface contributes to the softness. The light source becomes larger—but also farther away.
Both factors influence the softness of the light, and they also affect how quickly light falls off on the model.In test 1, the collar and shoulder are the brightest parts, with rapid light falloff. In image 2 below, a larger area on the model is evenly lit.
Of course, light will also spread to the background and the room, but what happens on the model’s face compared to test 1? Surprisingly little, in terms of softness. Despite the greater distance, we still retain the light's softness.
So what can we learn from this? What I take away is what an amazing tool this simple light modifier really is. We can place the umbrella very close for distinct exposure changes, or place it farther away for more even exposure thanks to its light-spreading properties.
Especially when shooting through, the convex shape creates a gentle “fade” into the unlit areas. This makes the transparent umbrella a perfect light source when blending flash with ambient light, such as daylight outdoors or portraits in an office.
However, a shoot-through umbrella does not produce softer light than a reflective umbrella of the same size.
Shoot-through umbrella.
Light source is close to the model, resulting in fast exposure falloff.
Reflective umbrella.
Light source is farther away, resulting in more even exposure and a slightly brighter background. However, light softness remains equivalent.
If I now decide to repeat the test but move the flash farther from the model, what happens then?
With distance, the difference in softness/hardness between reflective and shoot-through umbrellas diminishes (i.e., the light-to-shadow gradient). However, the falloff from light source to ambient or unlit areas becomes smoother with a shoot-through umbrella.
With this new understanding of how light softness behaves, why do we need different types of umbrellas?
Just like any other light modifier, it depends on the desired result. In my case, I’d choose a shoot-through umbrella when I want to blend the light seamlessly with existing light—flash, daylight, or continuous light—to create the illusion of “natural light.” A shoot-through umbrella gives me such a soft transition that it becomes nearly impossible to tell where the flash ends or begins—especially when combined with other light sources.
In other words, outside the studio, a shoot-through umbrella is my “go-to” light modifier if I had to pick just one. For me, the Deep Transparent Umbrella 105 cm is an excellent choice—easy to carry, and its deep shape makes light fade even more gently. I mostly use a reflective umbrella when I want to use the flash's power as efficiently as possible while still enjoying the benefits of umbrella lighting. It’s the opposite of how a deep transparent umbrella gently fades the light— a deep reflective umbrella concentrates the light and enhances its efficiency.
When it comes to softness or hardness of light, it actually doesn’t make much difference whether you choose a shoot-through or reflective umbrella.
I hope this test has made it a bit easier for you to decide which umbrella to use and when. It certainly has for me.
/John