Stroboscopic flash in portrait photography: technology, accessories and application examples

From WhiteWall expert Katharina Wergen

You’ve probably seen these types of images, even if you haven’t heard the name before: stroboscopic flash photos are fascinating and impactful, often reminiscent of a time-lapse effect as they capture motion or sequential actions.

The stroboscopic flash effect is a captivating technique in photography that allows motion to be shown multiple times within a single image. This is achieved through a series of short, repeated bursts of light triggered during a long exposure.

This method enables creative and striking portraits in which, for example, the movement of a person is made visible within a single shot. But how exactly does a stroboscopic flash work, and what equipment is needed to use this technique successfully?

What is a stroboscopic flash and how does it work?

The stroboscopic flash effect occurs when a flash unit emits multiple bursts of light at very short intervals. These short pulses are typically fired at fixed intervals of a few milliseconds, making a moving subject appear in several stages of motion within one photo.

Imagine capturing dancers in mid-turn. During a long exposure, and with the help of the stroboscopic flash, each phase of their movement can be recorded. The result is a kind of motion sequence that highlights movement and dynamics while giving the image its own unique aesthetic.

Essential equipment for portraits with stroboscopic flash

To create portraits using stroboscopic flash, you need specific gear. Here are the key components and their purposes:

1. Stroboscopic flash unit

The core of this technique is a stroboscopic-capable flash unit. This can be a special external flash with a built-in strobe mode or a studio flash with the appropriate settings. When choosing a suitable flash, it’s important to ensure it can emit fast bursts at fixed intervals and that the flash frequency (measured in hertz) can be adjusted.

Example: A studio flash that can fire up to 20 bursts per second is ideal for capturing fast-moving subjects.

2. Camera with long exposure capability

To achieve the stroboscopic effect, you need a camera that supports long exposures. This allows all flash bursts to be captured in a single frame. An exposure time of several seconds is often necessary to make room for multiple flashes.

Tip: Set your camera to manual mode and choose a long exposure time, such as 2 to 5 seconds, depending on how many motion steps you want to capture.

3. Tripod for stability

A tripod is essential when using long exposures. It keeps the camera steady throughout the shot, which is crucial for sharp and precise results.

4. Remote or wireless shutter release

A remote trigger allows you to take the shot without touching the camera, preventing unwanted vibrations. This is especially helpful when shooting complex motion and needing precise control of the flash.

5. Light modifiers and reflectors

In portrait photography, light modifiers such as softboxes or beauty dishes help to soften and evenly distribute light. Reflectors can be used to fill in shadows and enhance the subject's visibility.

Calculating exposure time and flash frequency for stroboscopic portraits

To create stunning stroboscopic portraits, it’s important to set the correct values for both exposure time and flash frequency (in hertz). Here’s a simple guide to help you calculate and fine-tune these settings:

1. Calculating flash frequency (hertz)

Flash frequency determines how many times the flash fires per second. If you know how many distinct motion phases you want to capture, you can calculate the needed frequency as follows:

Example: You want to capture a dancer in 5 positions. The frequency f can be calculated using the number of flashes n and exposure time t:

f = n / t

If you want 5 flashes over a 2-second exposure:

f = 5 / 2 = 2.5 Hz

This means the flash must fire 2.5 times per second to create 5 visible positions in the photo.

2. Determining exposure time

Exposure time t can also be calculated using the number of flashes n and the flash frequency f:

t = n / f​

If you set the frequency to 2.5 Hz and want 5 flashes:

t = 5 / 2.5 = 2 seconds

This ensures that the camera captures all flashes during a single exposure.

Practical implementation

• Camera settings: Use manual mode (M) and set the calculated exposure time.

• Flash settings: Set the flash unit to the appropriate frequency.

• Test shots: Take a few test images to check that the motion steps are spaced correctly and that the flashes are synced.

Important notes

• Flash spacing: Lower hertz values result in more space between motion steps. Higher values produce smoother, more fluid movement.

• Light amount: Longer exposures can capture more ambient light, possibly leading to overexposure. Adjust ISO and aperture accordingly to avoid this.

Creative applications in portrait photography

Using stroboscopic flash in portraiture opens up a range of creative possibilities:

1. Capturing movement and dynamics

A classic stroboscopic use is capturing a model’s sequential motion. For example, if the model spins or jumps, the multiple flashes reveal each stage of movement. The result is a dynamic and artistic portrait that presents motion as a unified visual sequence.

Example: A dancer spinning can be photographed at various points in their movement, resulting in an almost cinematic effect.

2. Athletic and sports portraits

Stroboscopic flash can also enhance athletic portraits by showcasing power and motion. A sports figure performing a strike or jump can be captured at multiple phases, giving viewers a vivid impression of speed and precision.

3. Experimental portraits

Stroboscopic flash is perfect for experimental portraiture. For instance, you might capture various arm or torso movements of a model to create an image that appears to show a multiplied version of the subject. This is great for creative projects that aim to break from conventional portraiture.

Technical tips for beginners

• Set flash frequency: Choose your frequency based on how many steps of motion you want. Higher frequencies create more positions within a shorter time.

• Adjust exposure time: Make it long enough to include all desired flashes, but not so long that motion blur ruins the image.

• ISO and aperture: Keep ISO low to reduce noise. Aperture should be adjusted to control depth of field and prevent overexposure.

Beyond portraits: other applications of stroboscopic flash

Stroboscopic flash isn’t just for portraits – it can be used in many other creative photography contexts:

• Capturing moving objects: Things like falling water or bouncing balls can be frozen in each phase using this technique, with stunning results.

• Dance and theater photography: The flash can dramatically visualize choreography and stage movement, turning a performance into a visual sequence.

• Artistic still life: Even still subjects like rotating or swinging objects can become surreal compositions with motion rendered through stroboscopic exposure.

Printing tips for stroboscopic images

Stroboscopic images stand out through their dynamic motion, strong contrasts, and glowing light edges. To fully showcase these qualities, the right print medium is key. WhiteWall offers premium options that do justice to these special shots:

1. Glossy acrylic prints for contrast and brilliance

Acrylic enhances color and sharpness, highlighting the glowing edges and dynamic lighting typical of stroboscopic shots. It adds depth and a three-dimensional feel that suits this visual style.

Recommendation: Choose photo print behind acrylic for maximum brilliance and detail. The acrylic layer also protects the image and ensures its vibrancy even in bright spaces.

2. Alu-Dibond for minimalist presentation

If you prefer a lighter, more minimal option, Alu-Dibond is ideal. It offers a modern matte look that reduces reflections while still preserving contrast – great for large-format or gallery-style presentations.

Recommendation: A photo print on Alu-Dibond combines sleek style with sturdiness, perfect for clean, contemporary displays.

3. Fine Art prints for subtle detail

For black-and-white or more artistic images with nuanced detail, Fine Art papers like Hahnemühle, Epson, or Canson are ideal. These matte or textured papers offer deep contrast and tactile quality.

Recommendation: Fine Art prints deliver refined color rendering and a premium feel – perfect for turning your stroboscopic images into gallery pieces.

Conclusion

Stroboscopic flash is a versatile tool that goes far beyond traditional portraiture. It allows photographers to multiply motion and create dynamic effects that make images come alive. With the right gear, a bit of practice, and creative vision, you can craft compelling shots that capture attention and imagination.

WhiteWall offers premium print options to present your stroboscopic photography in the best possible light – whether in brilliant acrylic, minimal Alu-Dibond, or refined Fine Art paper. Your work will shine in gallery quality and leave a lasting impression.