Experimenting with UV Photography

Trying Out the Multispectral Camera with a ZB1 Filter to Block Visible and IR Light

Multispectral imaging opens a window into worlds we simply can’t see with the naked eye. Recently at Philip M Russell Ltd, we’ve been experimenting with UV-only photography, using our multispectral camera paired with a ZB1 filter — a specialist filter designed to cut out all visible and infrared light, leaving only ultraviolet wavelengths to reach the sensor.

The result is a fascinating blend of science, technology and art. What looks ordinary in daylight suddenly reveals hidden textures, markings and materials that only show up under UV illumination.

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Why Use UV Photography?

UV photography is ideal for science teaching because it exposes properties that students often only read about:

• Fluorescence and absorption in organic materials

• Surface coatings on plants, plastics and minerals

• Sunscreen effectiveness (fantastic demonstration!)

• Biological features like veins in leaves or pollen patterns

• Damage or repairs invisible under normal light

• Security markings on currency and documents

A multispectral camera allows us to make these invisible features truly visible.

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What the ZB1 Filter Does

The ZB1 filter is designed to pass UV light while blocking everything else:

• No visible wavelengths

• No infrared spill

• No mixed-spectrum contamination

This means the image captured is genuinely UV-reflective, not a mixture of UV and visible light — perfect for demonstrations in physics, biology, materials science and forensic-style experiments.

With the ZB1 attached, the camera essentially “sees” a world dominated by UV reflectance patterns.

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Equipment Setup

To capture clean UV images, our workflow includes:

1. Multispectral camera

A converted camera without the standard internal UV/IR cut filter.

2. ZB1 filter

Mounted at the front of the lens to isolate the UV band.

3. Strong UV lighting sources

UV LEDs or lamps — never sunlight alone — because the ZB1 blocks everything except deep UV.

4. Safety equipment

UV photography must be done responsibly:

• UV-protective goggles

• gloves when handling strong emitters

• careful positioning to avoid reflected UV

• a photodiode UV monitor (our own in-house build)

Safety is part of the lesson.

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Early Experiments

Some of the most striking early tests include:

• Flower petals — patterns invisible to human eyes but obvious to pollinators

• Leaves — UV absorption revealing internal structures

• Fabrics — dyes reacting differently under UV, helpful for forensic teaching

• Sunscreen — instantly visible as a dark, UV-absorbing layer

• Skin texture — showing sun damage or pigmentation variations

Each of these makes a wonderful visual teaching moment for students studying light, materials, biology or photography.

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Challenges in UV Photography

It’s not as simple as pointing and shooting.

• UV light levels are low → exposures must be long

• Focusing is hard → many lenses shift focus in UV

• Noise increases → sensors aren’t optimised for UV

• Light spreads differently → some scenes look flat

• Filters cut so much light → strong illumination is essential

But these challenges are part of what makes it a perfect teaching tool — students see that physics principles really matter.

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Why UV Imaging Is Valuable in Teaching

UV photography bridges multiple subject areas:

• Physics: electromagnetic spectrum, energy, filtering

• Biology: pollination, plant structure, skin response

• Chemistry: fluorescence, absorption, molecular interactions

• Media: multispectral imaging, specialised lighting

• Forensic science: hidden patterns and markings

A single UV session generates material for lessons across several subjects — and some beautiful, surprising images for social media and video.

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The Takeaway

Experimenting with UV photography using a multispectral camera and a ZB1 filter reveals details that remain hidden in the visible world. It’s a captivating way to bring science alive and teach students to think beyond the ordinary spectrum.

More tests to come — and plenty of ideas for how to use UV imagery in upcoming videos and lessons.