The Problem With Visible Light
Every photograph you have ever taken records a narrow slice of the electromagnetic spectrum — roughly 400 to 700 nanometers, the range your eyes can see. But your camera sensor is sensitive to a much broader range. Infrared radiation, wavelengths from about 700nm to 1200nm, hits the sensor just as light does. Camera manufacturers install an IR-blocking filter directly over the sensor to prevent this invisible radiation from contaminating your visible-light images.
Infrared photography asks a different question: what if you blocked visible light instead and recorded only the infrared? The result is a world transformed. Green foliage glows white. Blue skies darken to near-black. Skin takes on a smooth, porcelain quality. The familiar becomes alien, and landscapes that looked ordinary under visible light reveal a strange, luminous beauty that exists just beyond what your eyes can perceive.
The challenge is that you are working against your camera’s design. The IR-blocking filter is there precisely to prevent what you are trying to achieve. Getting around it requires either very long exposures through an external IR-pass filter, or a permanent hardware modification. Both approaches work, but they demand different levels of commitment and produce different quality results.
What This Technique Is
Infrared photography captures electromagnetic radiation in the near-infrared spectrum, typically between 700nm and 1000nm. This radiation is invisible to the human eye but interacts with the physical world differently than visible light. Materials that appear dark in visible light may be highly reflective in infrared, and vice versa.
The technique produces images with a distinctive tonal signature. The most recognizable characteristic is the Wood effect, named after physicist Robert W. Wood, who first photographed it in 1910. Healthy vegetation reflects approximately 50 percent of incoming near-infrared radiation due to the internal cellular structure of leaves, making foliage appear brilliantly white. Sky, which scatters visible blue light but transmits infrared, appears very dark. Water can appear either bright (if reflecting IR-bright foliage or clouds) or dark (if reflecting IR-dark sky).
There are two primary workflows. Filtered IR uses an unconverted camera with an IR-pass filter mounted on the lens. The camera’s internal IR-blocking filter absorbs most infrared, so only a small fraction reaches the sensor, requiring extremely long exposures. Converted IR uses a camera that has been professionally modified to remove the internal IR-blocking filter, allowing the full infrared signal to reach the sensor. This enables normal shutter speeds and handheld shooting.
Essential Gear
IR-pass filter (for unconverted cameras). A 720nm filter is the most versatile starting point. It passes deep red and infrared, producing images that can be processed as either false color or black-and-white. An 850nm filter passes only infrared and produces inherently monochrome results. Budget alternative: used IR filters from previous generations are widely available and optically identical to current models.
Converted camera (for serious IR work). A dedicated IR conversion by a reputable service costs between $250 and $400 for a crop-sensor body. Many photographers convert an older camera body rather than their primary camera. A 720nm conversion is the most popular choice, offering flexibility between false color and monochrome processing.
Tripod (essential for unconverted cameras). Exposures through an IR filter on an unconverted camera can range from 30 seconds to 4 minutes, making a tripod mandatory. Converted cameras can shoot handheld at normal shutter speeds.
RAW-capable camera. Infrared images require significant white balance and color channel manipulation in post-processing. RAW files provide the 12 to 14 bits of color data needed for clean adjustments. JPEG infrared images will break apart quickly under heavy processing.
Lens with minimal IR hot spots. Some lenses produce a bright circular artifact in the center of IR images, caused by internal reflections of infrared radiation between lens elements and the sensor. Test your lenses before committing to a shoot — hot spots vary by lens design and aperture. Older manual-focus lenses often perform better than modern autofocus designs.
Core Settings
| Scenario | Aperture | Shutter Speed | ISO | Filter/Conversion | Notes |
|---|---|---|---|---|---|
| Landscape (converted, 720nm) | f/8 | 1/125–1/500 sec | 200 | 720nm conversion | Normal shooting speeds |
| Landscape (unconverted + filter) | f/8 | 30–120 sec | 200 | 720nm screw-on | Tripod required |
| Portrait (converted, 720nm) | f/4 | 1/250 sec | 200 | 720nm conversion | Skin appears smooth |
| Architecture (converted, 850nm) | f/11 | 1/60–1/250 sec | 200 | 850nm conversion | Strong contrast, mono only |
| Forest canopy (converted, 720nm) | f/5.6 | 1/125 sec | 200 | 720nm conversion | Peak Wood effect |
Step-by-Step Execution
Step 1: Set a custom white balance. Before shooting, photograph a patch of sunlit grass or green foliage through the IR filter (or with the converted camera). Use this image to set a custom white balance in-camera. This shifts the raw capture from an overwhelming red/magenta cast to a more workable palette of warm yellows and cool blues. Without this step, every image will appear as a solid wall of deep red.
Step 2: Focus before filtering (unconverted cameras only). Infrared light focuses at a slightly different distance than visible light. If you are using a screw-on IR filter on an unconverted camera, compose and autofocus before attaching the filter. Then switch to manual focus and carefully apply the filter without disturbing the focus ring. Some older lenses have a red IR focus mark on the barrel — shift focus to this mark after locking visible-light focus.
Step 3: Compose for tonal contrast. In infrared, your composition tools are tonal rather than color-based. Look for scenes where bright IR subjects (foliage, grass, certain fabrics) are juxtaposed with dark IR subjects (sky, water reflecting sky, stone, asphalt). This tonal contrast is the visual engine of infrared photography.
Step 4: Expose to the right. The histogram of an IR image will look different from a visible-light image — often weighted heavily to the right due to the brightness of vegetation. Push the exposure as far right as possible without clipping to maximize the data captured in bright tones. This reduces noise in the converted image and gives you more processing flexibility.
Step 5: Process the RAW file. Open the RAW file and start with white balance correction. Adjust the temperature and tint sliders until foliage appears white or pale yellow and sky appears blue or dark. For false color IR, swap the red and blue channels in your photo editor’s channel mixer. This produces the classic blue-sky, golden-foliage look. For black-and-white IR, convert to monochrome and adjust the channel sliders to control the relative brightness of foliage, sky, and other elements.
Step 6: Refine contrast and detail. Infrared images often appear soft due to the diffraction of longer wavelengths. Apply moderate sharpening. Increase contrast to emphasize the tonal separation between IR-bright and IR-dark elements. Be careful with shadows — IR images can have unusual noise patterns in dark areas that aggressive processing will amplify.
Creative Variations
False color infrared. After swapping the red and blue channels, you get a surreal palette: deep blue skies, bright golden or white foliage, and warm skin tones. This look has been popular since the days of Kodak Ektachrome Infrared slide film, which produced similar color shifts on the chemical emulsion. It works best in sunny conditions with blue sky and abundant vegetation.
Black-and-white infrared. Converting the processed IR image to monochrome produces ethereal landscapes with glowing white foliage, dark skies, and strong atmospheric contrast. This look is closely associated with the work of Minor White and has a timeless, dreamlike quality. Dark red filters (850nm+) produce the highest contrast and most dramatic results.
Infrared portraiture. Skin appears smooth and almost translucent in infrared because IR radiation penetrates the top layer of skin slightly before reflecting. Veins and blemishes become less visible. Eyes appear dark and striking against the brightened skin. The effect is unusual and can range from ethereal to unsettling depending on the processing.
Mixed visible and IR (full-spectrum). With a full-spectrum converted camera and no filter, both visible light and infrared hit the sensor simultaneously. The resulting images have an unusual color palette that blends both spectrums. Adding a light IR-pass filter like a 590nm allows some warm visible light through alongside the infrared, producing rich false colors with more tonal variety than a pure 720nm filter.
Troubleshooting
Problem: A bright hot spot appears in the center of the image. This is an IR hot spot caused by internal reflections in the lens. Stop down to f/11 or narrower — hot spots often diminish at smaller apertures. If it persists, that lens is not suitable for IR. Prime lenses with simpler optical designs tend to perform better than complex zooms.
Problem: Images are entirely red or magenta. You have not set a custom white balance. The camera’s auto white balance cannot compensate for the extreme spectral shift. Set a manual white balance using sunlit foliage as a reference, or correct it in post-processing using the RAW white balance sliders.
Problem: Foliage is not glowing white. You may be shooting in the wrong season or conditions. The Wood effect depends on living, healthy vegetation. Dry or dead foliage reflects much less IR. Evergreens reflect less than deciduous leaves. Shoot in spring or summer when foliage is at peak health and chlorophyll content is high.
Problem: Images are very noisy. On unconverted cameras, the extremely long exposures needed for IR generate significant thermal noise. Enable long exposure noise reduction in-camera. On converted cameras, noise is usually caused by underexposure — remember to expose to the right. Also check that you are shooting at the camera’s base ISO (typically 100 or 200).
Problem: Autofocus is inaccurate on a converted camera. IR focuses at a different point than visible light. Most conversion services offer autofocus recalibration as part of the conversion. If your converted camera was not recalibrated, you will need to use manual focus with live view at high magnification. Using live view focuses based on what the sensor actually sees, which is now infrared.
ShutterCoach Connection
Infrared images push the boundaries of what standard critique frameworks evaluate, and ShutterCoach adapts its analysis accordingly. When you share an IR photograph, the feedback focuses on tonal composition and contrast rather than color accuracy, evaluates your use of the Wood effect for visual impact, and checks for technical issues like hot spots and focus accuracy. As you build a portfolio of IR work, the feedback tracks your progress in mastering both the capture and the distinctive post-processing that infrared demands.