See the Unseen: A Practical Guide to Infrared Photography with IR Pass Filters

See the Unseen: A Practical Guide to Infrared Photography with IR Pass Filters

Imagine turning a bright summer day into a surreal, dreamlike scene where green leaves glow white and the sky turns a dramatic, inky black. This isn't a complex editing trick—it's the magic of infrared (IR) photography. Using a simple IR pass filter on your existing camera, you can capture a hidden world of light that our eyes can't see, creating images that are both striking and otherworldly.

What Does an IR Pass Filter Actually Do?

Think of an IR pass filter as a special gatekeeper for light. It blocks most of the visible light that your camera is designed to see and allows only invisible near-infrared (NIR) light to pass through to the sensor.

When your camera records this NIR light, the world is transformed:

• Foliage like leaves and grass reflects IR light intensely, making them appear bright white or silver.
• Skies and Water absorb IR light, rendering them dark and full of contrast.
• Skin takes on a soft, smooth, and ethereal quality.
• Haze and Fog are cut through, revealing crisp details in distant landscapes.

You can use a screw-on IR filter with a standard, unconverted camera, but you'll need much longer exposure times. For the best results, a full-spectrum converted camera (which has its internal IR-blocking filter removed) will give you sharper images, shorter exposures, and more predictable results.

Choosing Your Creative Style: 720nm vs. 850nm vs. 950nm

The number on an IR filter, like '720 nm', tells you where it starts letting in infrared light. This "cut-on" point dramatically changes the look of your photos.

• 720 nm: The Versatile Artist (Great for False-Color) This is the most popular choice and the perfect starting point. It lets in a tiny bit of deep red visible light along with the IR, which allows you to create stunning "false-color" images by swapping color channels in post-processing. It gives you bright white foliage, dark skies, and requires the shortest exposure times of the three.
• 850 nm: The Classic Black & White Powerhouse This filter cuts out almost all visible light, creating images with intense punch and contrast. Because there's very little color data, it’s ideal for photographers who want to create bold, dramatic monochrome landscapes. Exposures will be longer than with a 720 nm filter.
• 950 nm: The Deep IR Specialist For the true IR purist, this filter blocks everything except deep infrared light. It requires the longest exposures and is best used on a full-spectrum camera. Its main advantage is in technical applications or for shooting at night using an IR illuminator (like those used for wildlife photography), where you want to capture a scene without any visible light.

Our recommendation? Start with a 720 nm filter for creative flexibility or an 850 nm if you know you love high-contrast black and white.

Your Step-by-Step Setup for Success

Shooting in IR can be frustrating if you aren't prepared. Follow these steps to avoid common issues like soft focus and strange colors.

1. Use a Tripod: Especially with a non-converted camera, your shutter speeds will be several seconds long even in bright daylight. A sturdy tripod and a remote shutter release are your best friends.
2. Set a Custom White Balance: Your camera's auto white balance won't work. Point your camera at something that will be bright white in IR—like green grass or healthy foliage—and set a custom white balance. This gives you a better starting point for editing.
3. Shoot in RAW: This is non-negotiable. RAW files give you the flexibility to adjust white balance and exposure later and to manage the high-contrast tones typical of IR.
4. Nail Your Focus: Infrared light focuses on a slightly different plane than visible light. Your autofocus might not be accurate. The best way to get sharp focus is to use your camera's Live View, magnify the image on screen, and focus manually. Using an aperture of f/5.6 to f/11 will also help ensure everything is sharp.

Creative Ideas for Infrared Photography

• Transform Landscapes into Dreamscapes: This is the classic use. Turn midday sun into a dramatic scene with white trees and a near-black sky.
• Minimalist Architecture: The deep contrast between buildings and the sky makes geometric shapes pop. Long exposures can blur out clouds and people for a clean, minimalist feel.
• Silky Smooth Water: Combine the light-blocking effect of an IR filter with a long exposure to turn rivers and oceans into smooth, misty surfaces, even in the middle of the day.
• Ethereal Portraits: IR light is incredibly flattering on skin, giving it a soft, glowing look. A 720 nm filter works well to retain a hint of color for creative effects.

Troubleshooting Common IR Problems

• The Dreaded "Hotspot": See a bright, soft spot in the center of your photos, especially at smaller apertures like f/8 or f/11? This is a hotspot, caused by internal reflections in your lens that are visible in IR. Before you shoot, test your lenses or consult an online [IR lens hotspot list].
• Weird Color Casts: If you're struggling with colors using a 720 nm filter, don't fight it. Convert the image to black and white and focus on creating a powerful monochrome edit.
• Unreliable Metering: Your camera's light meter can be easily fooled by infrared light. Trust your histogram, not the meter. Expose your image so that the brightest parts (the highlights) aren't blown out.

Not All Filters Are Created Equal: What to Look For

When choosing an IR filter, the specs matter for your final image quality. A cheap, low-quality filter can ruin a great shot. Here’s what makes a KUPO Optics filter a reliable professional tool:

• High IR Transmission (~85-95%): Our filters let through a maximum amount of IR light, meaning your exposures can be shorter and cleaner.
• Strong Visible Light Blocking: We ensure that unwanted visible light is blocked out (typically OD≥3), which prevents color contamination and keeps your IR images pure and contrasty.
• Premium Optical Glass: We use high-quality BK7 or B270 glass, built to a thickness of 1.0−2.0 mm for durability and sharpness. A perfectly flat, polished surface (≤λ/4 @ 633 nm) means your images will be as sharp as your lens allows.
• Advanced Anti-Reflective (AR) Coatings: This is critical. Our NIR AR coatings dramatically reduce reflections that cause flare and lens hotspots, giving you cleaner, higher-contrast images.

Ready to Explore the Invisible?

IR pass filters open up a completely new dimension in photography. By choosing the right filter, mastering your setup, and using high-quality coated optics, you can reliably create breathtaking images that stand out from the crowd.

Explore our full range of [Infrared pass filters (720–950 nm)] or [Download the IR filter datasheet] to get all the technical details.

Have a specific project in mind? Request a sample or a custom size today. Our team is ready to help you spec the perfect filter for your creative vision.