There are several ways to capture black-and-white images with a digital camera. The most straightforward is to shoot with any standard digital camera and convert the images to black and white in post-processing. Leica also makes cameras equipped with a sensor that has no colour filter array, delivering a native black-and-white image straight from the camera. The third option — and the one I want to explore here — is digital black-and-white photography without an IR cut filter. This involves physically removing the IR cut filter that sits in front of the sensor. I will explain how it works and show you how to achieve results that stand apart from conventional black and white photography. Strictly speaking, this method can produce more than just black and white images. It also opens up the world of false-colour infrared photography. I won’t go into that here, but it can lead to equally striking results.
How Do I Remove the IR Cut Filter?
Removing the IR cut filter is unfortunately not a simple task, and you should not attempt it yourself. The filter sits deep inside the camera. Directly in front of the sensor, which means the camera has to be completely disassembled. This is a job for specialists who know exactly what they are doing. Fortunately, there are a number of companies that offer this conversion for a modest flat fee. One example is IRrecams.de. You will also find more detailed information about what else is possible with a camera that has had its IR cut filter removed. In this article, I will focus specifically on black and white photography.
A Tip for Trying It Out First
If you want to find out whether this style of photography is for you before committing to a conversion, you can use a standard camera with an IR pass filter attached to the lens. Most digital cameras retain a small degree of IR sensitivity even with the IR cut filter in place. The downside of this approach is very long exposure times, since only a tiny fraction of light reaches the sensor. The Leica M8 is particularly well suited to this method — thanks to its unusually thin IR cut filter, it has a notably higher native IR sensitivity than most cameras.
What Else Do You Need?
By removing the IR cut filter, the sensor becomes sensitive not only to visible light but also to infrared and ultraviolet wavelengths. You can therefore use specific filters to restrict which part of the spectrum reaches the sensor, giving you direct control over the look of your images. I use clip-in filters from STC that you can swap yourself. There are three variants to choose from: IR pass filters that transmit wavelengths from 590 nm, 720 nm, or 850 nm upwards. Depending on which you use, you will get quite different results. (If you are not yet familiar with wavelengths, a photography basics resource can help clarify things.) True infrared light begins beyond 700 nm, so for black-and-white IR photography, I use either the 720 nm or the 850 nm filter. If you want to try the false-colour variant, the 590 nm filter is the one to reach for — it still lets through a significant amount of red visible light, which produces the characteristic false-colour effect.
A Few More Things to Keep in Mind
If you are still using a DSLR, you will need to recalibrate the autofocus. Infrared light focuses at a slightly different plane than visible light, and DSLR autofocus systems use a dedicated AF sensor that only sees visible light. Mirrorless cameras, on the other hand, focus using the same sensor that captures the image, so no recalibration is needed.
When shooting, always work in RAW format and set the white balance manually. The camera’s entire processing pipeline — including automatic white balance — is calibrated for a sensor with an IR cut filter in place, so auto white balance will no longer produce correct results. Shooting RAW at least gives you the flexibility to adjust white balance in post. Other automatic functions may also behave unexpectedly, so be prepared to experiment and, where necessary, switch to fully manual settings.
Conclusion
I had an old Olympus E-M1 converted and use it occasionally for this kind of photography. It is particularly enjoyable for landscape work, where there is often a lot of vegetation — IR light makes foliage glow brilliantly in a way that is impossible to replicate in standard black and white. I would love to hear about your experiences in the comments below. If you have a website where you cover this topic or share your IR images, feel free to drop a link and I will be happy to add it here.