How to Use Infrared Filters for Stunning Photos

What is infrared, you ask? All light we see exists in the form of electromagnetic waves. The wavelengths, or frequencies, are capable of transmitting different intensities that sit within the boundaries of ‘visible’ light.

But the human eye isn’t perfect and certain frequencies aren’t available to our natural perception. Above this ‘visible’ spectrum of light we have infrared light, sometimes referred to as IR. While at the lower end of the spectrum, we have ultraviolet light (UV).

For example, we can see light in approximate wavelengths between 400 and 700nm (measured in nanometers). Infrared filters typically cut out all the wavelengths below 720nm, meaning you can access the invisible light in the infrared wavelength range.

Although there is an entirely invisible world of colour and contrast out there, we’re able to access it photographically with the assistance of an infrared filter on your lens. The results can be hauntingly beautiful, rendering any scene with a ghostly appearance.

Infrared filters are an exciting and welcome addition to your photography kit as they allow a greater pursuit of creativity. Keep reading to learn more about infrared filters and how to use them.

Most digital cameras are capable of reading infrared light, but first you need to remove the infrared-blocking filter from your sensor so it becomes a dedicated infrared light camera. This is somewhat like elective surgery for your camera and generally involves posting it to a specialist to perform the operation. Once you’ve done that, you can attach an infrared filter onto your favourite lens to capture stunning infrared photos.

In terms of photographic process, nothing changes except for your consideration of how colours may be rendered differently. For example, leaves and other foliage are significantly changed when viewed under infrared light due to photosynthesis. And blue skies can become a dramatic inky black. For this reason, photographing on bright sunny days is generally the best to unlock the full otherworldly potential of infrared photography.

Most creative lens filters have a few tricks to their operation and the infrared filter is no exception. What do you expect when you’re trying to photograph the invisible!

The infrared filter is notoriously dark, making it near impossible to see through. For this reason, handheld images are out of the question. You can expect to be slowing your exposures right down to allow enough light to pass through the filter, so get yourself a sturdy tripod and even a cable release if you prefer to be completely hands-free. To ensure there’s a usable image, some photographers even recommend bracketing above and below i.e. taking an underexposed and overexposed image in addition to the normal exposure. Sometimes these three images or more are then blended in post-production to show greater dynamic range between the shadows and highlights.

To make sure you have a nice crisp photo with a composition you love, you will need to compose and set your focal point before threading the filter onto your lens. Due to the complete darkness of the infrared filter, it will simply be too difficult to see the scene with the filter already mounted.

As mentioned before, if you’re hoping to get the most out of your infrared filter and your time, check the weather to ensure sunny skies are on the way. Blue skies become eerie bright nights while the photosynthetic pigments in the greenery turn ashen.

Some lenses respond well to the use of an infrared filter, while others are more susceptible to lens flares (although this can create equally exciting results). Much like finding your lens's aperture sweet spot, you may need to experiment with different lens types to determine which responds best to infrared light. But as infrared filters are commonly used to capture lush foliage and blue skies, a wider landscape photography lens in the 16–35mm range is a good starting point.

Your camera settings will be much the same. If photographing outdoors and wanting to render the scene with the appearance of sharpness from front to back, use a narrower aperture of f/11 while keeping your ISO low. Your shutter speed will be compromised due to the infrared filter cutting so much available light so be sure to adjust accordingly and increase your ISO or widen your aperture if compensation is needed.

This is perhaps where the workflow seems a little more complicated, but really, it’s quite easy, and fun!

Your out-of-camera images using an infrared filter are going to appear a little whack. Most of the time, infrared images are presented in black and white to really amplify the invisible light and the shift in tone. If you’re using Adobe Photoshop or similar software, simply apply a black and white conversion or adjustment. From here, have a play around with the curves if you want to further exaggerate the shadows and highlights.

If you want to create ethereal-like images as shown below, have a play around with the Channel Mixer settings in Adobe Photoshop, altering the Red and Blue channels to the desired effect.

You can read more about editing infrared images online, but we recommend simply exploring new possibilities through both the initial capture and your editing software.

What are you waiting for? Capture invisible light and make the world pause and ponder over your unique landscapes.

Urth offers infrared filters in thread sizes ranging from 37mm to 95mm. Shop the range here.

If you’re looking to stoke the fires of your photographic exploration through other special effects, be sure to check out Urth’s starburst and night photography filters.