Infrared Photography Tutorial

Infrared photography is famous for its fascinating surreal look that cannot be easily reproduced within the visible spectrum. Whether black and white or colour, these photos use high contrasts and ‘false colour’ to add extra definition and a dissonant yet attractive character to any composition. Using my recent experience with infrared photography, in this tutorial I explore how you can use your DSLR with an infrared filter to capture and process your own infrared photos.

What is Infrared?

Visible light represents a tiny portion of the electromagnetic spectrum (pictured below). On either side of visible light are Ultraviolet and Infrared waves, two wavelengths (or frequencies) of light that we can’t see with the naked eye. However, by using an infrared filter (or a converted sensor), we are able to capture some of this hidden light.

The waves or frequencies that we’re able to capture are unlike the infrared waves necessary for thermal imaging and night vision. In fact, infrared photography actually refers to NEAR-infrared photography, as the waves being captured by the sensor are much closer to the visible light spectrum than true infrared. To be specific, whereas thermal imaging and night vision use wavelengths 9000-14,000 nm long, our filters range from 590-850 nm. For comparison, the visible spectrum ranges from 400 to 700 nm.

Conversion vs. Filter

There are two ways to capture near-infrared photos and each method has it’s own advantages and disadvantages. By converting the camera’s sensor to capture infrared light only, you are able to sidestep the inconvenient long exposures necessary when using a filter. The primary drawback to this method is that this process is expensive and permanent. So, if you’re looking to get into infrared photography and want to take photos as you do normally (without a tripod, using auto-focus), you can use services from Kolari Vision to either convert your existing camera or buy a pre-converted infrared camera. However, for this tutorial we will be using a 720 nm infrared filter on an unconverted Nikon D800 with a 50mm 1.8 lens.

Tips to Capturing Amazing Infrared Photos

Although the majority of infrared effects are added in the post-processing stage, the following tips will help you know what to look for in an infrared composition and how to best capture them without effecting costly mistakes.

Shoot in RAW

To ensure your camera sensor is picking up the most colour depth possible for your infrared images, make sure you are shooting in at least 14 bit RAW with an Adobe RGB profile. This will allow your camera to capture and save as much colour as possible, crucial when operating in a limited colour range. This colour profile will be instrumental in the post-processing stage where we create the ‘false colour’ effect and correct for proper exposure.

Weather

Direct sunlight? No problem! Infrared photography has the wonderful advantage of performing well under direct sunlight. In fact, it really doesn’t perform well when not in direct sunlight. If you want to achieve the dark blues and surreal contrasts of trees and vegetation, the more sun the better! The middle of the day is when I’ve taken my best infrared photos, but I’ve also had some success during the later afternoon and early evening.

Manual Focus Tips

Infrared light will focus at a slightly different setting than visible light. This may cause your images with a shallower depth of lower f-stop to appear slightly blurry. To combat this effect, set your focus using visible light (without the filter on) and then place the filter back on, taking photos while slightly adjusting the lens’ focus. While this is a cumbersome method, it shouldn’t take more than a few shots to master the difference in focus adjustments. If this is too much of an annoyance, perhaps you should consider a infrared camera conversion.

Best Lens Choices

As mentioned above, not all lenses are equal when it comes to infrared. For example, my Nikon 50 mm 1.8 produces a centre hot spot especially at an f-stop lower than 2.8. To see if your lens is a good choice for infrared photography, the writers at LifePixel and Kolari Vision have compiled a list of lenses comparing their hot spots.

These are available here:

Lens Hot Spot Testing Database (Life Pixel)

Lens Hot Spot Testing Database (Kolari Vision)

Wavelength of Filter

As mentioned earlier, the wavelength of infrared varies greatly. Because of this, we have a variety of infrared filters that use different wavelengths to create different effects. The gold standard for near-infrared photography is 720 nm and is known for its white vegetation and cool blue sky. Other wavelengths such as 580 nm produce still more interesting effects including dark crimson rocks or navy blue skies. Have a look at Kolari Vision’s article which details the differences between filters. As I only have experience with the standard infrared filter, you can utilize their database for more information.

Viewfinder Cover

While an easy fix, this remains one of the most annoying yet easiest ways you can wreck an infrared photo. Ensure your viewfinder is closed when capturing a photo!

Custom White Balance Settings (on Camera)

Though not mandatory, to create the false-colours look with minimal post-processing, we can create a custom white balance setting on our camera. When I am doing this, I simply take a photo of grass (all green) and set this as my white balance (How do I create a custom white balance?). The logic of this setting is that it replaces the green in your image with white, producing a snowy white look on the trees.

Post-Processing

Once you’ve captured your image, you now can process your image on the computer for the ‘false colours’ infrared is known for.

What is False Colour?

False colour simply refers to the unique effect of infrared photography where we replace the captured colours of the photograph to better represent the visible spectrum. To imagine this better, try to imagine how thermal imaging works. The infrared sensor picks up light waves outside the visible spectrum and converts them to a gradient on the visible spectrum (show example photo below). You interpret this as being a heat map only because the designers chose to set that gradient in that way. In the same way, infrared photography is known not by how it appears on the camera without white balance adjustments, but by the way it is processed afterwards.

Before and After:

To achieve false colour is relatively simple, though the variety and intensity of colours are diverse. There is no ‘right’ way to achieve a proper infrared photograph, only more optimal ways to achieve these results.

1. White Balance

Depending on your settings, your captured photo may look like either of the photos shown above. In either case, you are going to want to adjust your white balance to correct the for the imbalances. When you open your image in RAW, if you haven’t used a custom white balance on your camera, drag the temperature and tint values to the left (lower) side. Adjust the values until you photo’s vegetation looks white. We can fine tune these adjustments in the next step.

Black & White Infrared

At this step you can decide if you’d like to finish your photo in black and white or in colour. For black and white, your job in Photoshop is easy. Navigate to image > adjustments > gradient map and apply a black and white gradient to your image. To fine tune your new composition, drag the middle slider on the gradient either direction to increase the contrasts.

2. Channel Swap

The most common first step in post-processing is the channel-swap. Essentially, we replace the red and blue channels to bring in colours that were non-existent or hidden. To do this in Photoshop, you must first create a “channel mixer” layer on top of your image. Once complete, set your RGB settings as follows.

Red Channel – R: 0%, G:0%, B:100%

Green Channel – R:0%, G:100%, B:0%

Blue Channel – R:100%, G:0%, B:0%

This may not work out perfectly and may require some finer adjustments with the values. As you can see in my example below, I had to add an extra 19% to Red in the Red channel to adjust for a untrue white balance. The next steps will also help you find the desired effect you are looking for.

3. Color Balance

Again, create a new editing layer, this time for “colour balance”. Adjust the values as per what looks good to you. I typically go for an image that has more magenta and deep blues, so play around until you see something you like.

4. Add Hue / Saturation

If you’re really looking to add some psychedelic effects to your images, adding a “hue / saturation” editing layer will be immensely helpful. I’ve used this in the past to colour certain areas of the image that I wanted to be in a particular range.

5. Fixing Hot Spots

As mentioned earlier, some lenses produce particularly noticeable hot spots at certain f-stops. To fix them in Adobe Photoshop, select the sponge tool with a large feathered brush and select desaturate. Hover over the hot spot and click a few times until the middle looks like the rest of the image. If needed, use the burn tool with “highlights only” selected and do the same process.

Conclusions

After following these steps you’ll be well on your way to creating some unique and fantastic infrared photographs without going through too much work. As you have realized by now, infrared photography is an incredibly powerful tool for creating high contrast black and white photographs or otherwise surreal and attractive colour compositions. Although it requires a good deal of time to capture and process these images, they are well worth the effort. So go out and try taking some infrared photographs today and post your results in the comments!

Infrared Photos for Sale