Table of Contents
- What Is Infrared Photography?
- Understanding Light and the Infrared Spectrum
- What Is «False Color IR» Photography?
- What can IR Photgraphy be used for?
What is infrared photography?
Infrared photography is a way of capturing the world just outside what our eyes can see—specifically, in the near-infrared range of the light spectrum. It might sound complicated, but the idea is pretty simple: you’re taking photos using light that’s normally invisible to us.
What makes IR photography so special is the way it transforms what looks ordinary —like trees, skies, clothing— into something completely surreal. And yet, all of it is already there, just hidden from our eyes.
Understanding light and the infrared spectrum
We’ve all seen diagrams of the electromagnetic spectrum in school, right? The visible spectrum runs from around 400nm (violet) to 700nm (deep red). Just beyond that, from 700nm to about 1000nm, is what we call near-infrared (NIR) light.
This isn’t heat (that would be far-infrared or thermal imaging), but reflected light. Due to the chlorophyll, plants reflect a huge amount of IR light —way more than they reflect in the visible range— which is why they show up so differently in infrared photos.
Explaining the physics behind the scenes
One of the most fascinating aspects of infrared light is how it interacts with different materials.
For example, a key detail is how water tends to appear black in infrared images. That’s because, unlike vapor, liquid water does absorb NIR light. So when you photograph a lake or the sea in pure infrared, it often looks like a deep black void, adding a dramatic contrast to your shots.
The images above show the same scene captured in both the visible spectrum (ViS) and in near-infrared (using a 760nm longpass filter).
Notice the subtle differences in the brightness of the vegetation. While some reflections on the water remain visible in NIR, details beneath the surface usually disappear.
Take a look at how only a few of the stones underwater are still visible, and how the sky’s reflection appears much darker in the infrared image.
Another example is how fog tends to clear out in near-infrared photography, because water vapor tends neither to reflect nor to absorb this kind of light. These wavelengths pass through easily, allowing the camera to “see through” misty conditions that would normally block our view.
Lastly, one important factor already mentioned above is that plants reflect a large amount of near-infrared light. That’s why, in the images shown, vegetation appears significantly lighter in infrared shots compared to those taken in visible light. Take a look on the following images for example, where NIR image presents the lighter vegetation tones, NIR + ViS (Autumnizer filter) presents a half way, and only ViS shows up as darker vegetation.
Understanding how different materials transmit or absorb infrared light helps a lot when planning your photos. It tells you what kind of subjects will stand out—or disappear—depending on the conditions and the wavelength you’re working with.
What is false color infrared photography?
The first thing people notice is the weird colors, especially how vegetation turns white or pink, and skies can turn deep blue or even black. That’s not magic, it’s just physics.
In traditional IR photography, people used filters like:
- 550nm – 690nm: These let in a bit of visible light, especially red or green. That’s what gives you those colorful false-color IR shots when you process them later. This is out of the scope of True Color Infrared, but you can get a look at Rob Shea’s Photography blog, who has been working on those for a long time.
- True Color IR Filters: with full-spectrum cameras, you can use colored filters to get false color results straight from the camera —no editing required. That’s actually the whole idea behind the name of this site.
What can IR Photography be used for?
While in True Color Infrared IR is primarily used to create artistic pieces, infrared imaging has a wide array of practical applications:
- Forensics: Revealing bruises, gunshot residue, or ink alterations invisible in visible light.
- Art conservation: Infrared reflectography helps uncover underdrawings in paintings or validate the age of historical pieces.
- Agriculture: IR sensors on drones detect plant stress, hydration levels, or disease.
- Archaeology: Detecting ancient roads, buildings, or land modifications under vegetation.
- Industrial inspection: Checking for moisture intrusion, structural weakness, or hidden features in materials.
Each of these applications depends on how different materials reflect NIR light, offering insights invisible to conventional photography.
Final Thoughts
Infrared photography lets you see the world from a new angle—literally beyond the visible. Whether you’re here for the science, the surreal aesthetics, or both, this is just the start.