Rob Shea is a well-regarded photographer in the infrared community, known for his informative videos and blog posts that demystify the medium's more challenging technical aspects in a concise, accessible way. In addition to providing detailed information and tutorials, Shea has developed his Infrared Profile Pack, Photoshop Actions and LUTs, all of which are available for free (Shea, 2022, p.315).
In Figures 1 to 5 (above), Shea demonstrates the variety of effects achievable with a full-spectrum converted camera, depending on the lens filter used.
Figure 1 was captured using a UV filter, allowing the camera to reveal the invisible sun damage on the subject's skin. This technique requires a UV-compatible lens, and the filter alone costs approximately £200, making this an impractical option for this project (Kolari Vision, 2017).
Figure 2 shows a full-spectrum image taken without any filter, capturing ultraviolet, visible, and infrared light. According to Shea, "These color casts can result in surrealistic images or images that appear just plain wrong to the human eye" (Shea, 2022, p.38).
Figure 3 features a highly saturated infrared photo taken with a 590nm filter, which allows infrared light and some longer wavelengths of visible light to pass through. Original images taken with this filter have a heavy red cast, but they are usually edited with a red/blue channel swap, resulting in rich blue skies and coloured vegetation (Shea, 2022, p.37).
Figure 4 presents a traditional infrared colour photograph with desaturated and subdued colours. The 720nm filter allows infrared light and a small amount of red light to pass, leaving scope for channel-swapping the colours during editing (Shea, 2022, p.34).
Figure 5 was originally taken using a 590nm colour filter but was later converted to black and white in Photoshop. I have previously used an 850nm filter to create monochrome infrared images, which only allows infrared light to pass while blocking all visible light. However, Shea's method of converting colour photos to monochrome has its advantages, as "more visible light will decrease the infrared look of an image but increase the tonal range available" (Shea, 2022, p.35).
I have purchased two variable infrared filters (for different lenses), which allow me to take photos from 530nm to 750nm by simply twisting them. This method is more practical, as I can quickly adjust my filter without needing to remove it or change my composition, and I don't have to carry multiple filters. The most I might need to carry is my second lens, with the filter permanently attached.
For a long time, people have sought to replicate the effect of Kodak Aerochrome, famously used in Richard Mosse's work documenting the war-torn Democratic Republic of the Congo (Shainman, 2020), as seen in Figure 6 (below). This captivating photograph features rolling hills of magenta, creating a stunning, otherworldly landscape. Shea explains, "With Aerochrome, infrared light renders as red, red light renders as green, green light renders as blue, and blue light is muted" (Shea, 2022, p.39).
Although Aerochrome has been discontinued and no colour infrared film is currently produced, digital alternatives are now available for those who missed out on this medium. New filters are constantly being developed, with the Kolari Vision IR Chrome filter being one of the most talked-about in the infrared photography community (Kolari Vision, 2019). Designed in collaboration with Yann Philippe (Figure 7), "IR Chrome is a dual-band infrared filter" (Shea, 2022, p.78), which allows blue light and infrared light to pass while blocking all other wavelengths. This filter enables photographers to capture images reminiscent of Mosse's work directly from the camera, eliminating the need for channel-swapping in Photoshop. According to Shea, omitting this step reduces the likelihood of colour-fringing effects at the edges between the sky and leaves (Shea, 2022, p.79).
Figure 8 showcases Shea's own image taken with the Kolari Vision IR Chrome filter, illustrating how sunlight and shade can impact the way colours are depicted. Foliage can range from pink to orange, and skies can vary from vibrant purple to natural blue or eerie cyan, depending on how the sunlight interacts with the camera. While I am interested in purchasing one of these filters, they are currently beyond my price range (Kolari Vision, 2019).
Although I may not be able to use an IR Chrome filter for the foreseeable future, I can still experiment with different colours through channel-swapping, a technique frequently used by Barnaby Attwell and many other infrared photographers. I have learned a lot about channel-swapping from Shea's blog (Shea, 2021), where he details various methods to manipulate an infrared photo's colours in Photoshop. Typically, the red channel is set to 100% blue and vice versa, but by also adjusting the green channel to red, blue, or a combination of the two, a wide range of colour effects can be achieved (Shea, 2021), as illustrated in Figure 9 (below). Shea has also created free downloadable Photoshop actions that simplify applying various channel-swapping settings. I have installed these and look forward to experimenting with them.
Channel-swapping is a form of "false-color processing" as Shea calls it (Shea, 2022, p.165). Besides remapping wavelengths from one colour to another, it involves assigning a colour to infrared wavelengths. Shea explains that "infrared and ultraviolet wavelengths of light captured by the camera sensor are stored as red or violet colors. Since we cannot see infrared or ultraviolet light, non-visible light does not have color. We can assign these wavelengths of light to more visually pleasing colors" (Shea, 2022, p.41).
The first step in false-colour processing is to set the white balance of the image, typically to a neutral-toned area of stone, white clouds, or even foliage. This adjustment causes the image to display orange skies and white or blue vegetation, which can then be swapped to bring the sky back to a more natural blue (Shea, 2022, p.218). However, Shea states, "It can be gratifying to nail down 'the blue sky look' common to
infrared images when first learning to process infrared photos. You are not limited to this style. An entire color palette is available to you" (Shea, 2022, p.165). Figure 10 (above) demonstrates this idea well, featuring vibrant, heavily saturated colours, creating an atmosphere reminiscent of both pop art and surrealism.
While I appreciate the unbridled creativity these vibrant colours can bring to an image, they may be too garish for my project about loss. My solemn theme requires more subdued images to allow my audience space for introspection, so I will mostly focus on editing my photos with a more subtle colour palette. Shea's channel-swap presets will provide a solid foundation to work from.
Another action that Shea has created applies the Orton Effect to images in Photoshop, as demonstrated in Figure 11 (below). This technique, developed by Michael Orton, involves combining two transparencies of a scene - one sharp and underexposed, the other just out of focus and overexposed. James Abbott explains, "The result was an image that was both sharp and blurry with a dreamlike quality" (Abbott, 2021), and he compares the before and after of applying this effect to one of his photos (Figure 12).
Shea's Orton Effect action combines existing layers into a new one and duplicates it. This second layer has Gaussian blur applied and is set to an opacity of 25%. The opacity level can be adjusted to increase or reduce the effect (Shea, 2021).
When I started taking photos for this project, I struggled with focusing my camera. I read through Shea's blog and watched some of his YouTube videos, where I found the solution to my problem. In one video, "5 Pitfalls of Infrared Photography" (Shea, 2020a), Shea states:
DSLR and film cameras are calibrated to focus at visible light, they're not calibrated for infrared... you can have the autofocus calibrated to work with a specific lens in infrared. This will get you a good focus but it's very limiting because it means you're limited to using that DSLR with that single lens to get accurate focus with the autofocusing system.
I realised that, while the lenses I had were theoretically compatible with my camera, this did not account for the full-spectrum conversion process. I contacted the supplier of my converted camera body to find out which lens it had been calibrated to. Fortunately, it was the standard kit lens that would normally come with the camera, and I was able to purchase a second-hand one at a reasonable price. Suddenly, my images were sharp and I could focus more accurately!
Another aspect that compounded my difficulties with focus was diffraction. Shea explains on his blog that diffraction is a scattering of light that can reduce an infrared photo's sharpness. "Of particular importance for infrared photography, longer wavelengths of light, such as near-infrared, produce more diffraction compared to visible light wavelengths" (Shea, 2020b). To lessen the impact of diffraction, Shea recommends avoiding the use of the smallest apertures available. He elaborates in his book on the challenges posed by extremely small and large apertures for infrared photographers: "For lower f-stops, sharpness is reduced by depth of field. For higher f-stops, sharpness is reduced by diffraction" (Shea, 2022, p.136). This underscores the importance for photographers to be aware of their equipment's limitations and to compromise when choosing appropriate settings for their images.
Similarly, it is possible to encounter chromatic aberration due to light refraction - the bending of light as it passes through the lens. Shea explains in his book (Shea, 2022, p.125):
The refractive index for each wavelength results in colors focusing on different planes. This can be seen as color fringing at the edges between light and dark objects in visible light photography. Chromatic aberration is corrected in the lens for the center of the image but may be more pronounced near the corners.
Shea's videos, blog, and book offer a wealth of knowledge and experience, and even though I have only touched on some of it, I have learned a great deal. His explanations of focus, diffraction, and chromatic aberration have been particularly useful and have already improved my infrared photography skills. I feel better prepared to take more photos for this project, equipped with a deeper understanding of the technical aspects involved.
References
Abbott, J. (2021) Enhance detail and atmosphere with the Orton effect: James Abbott, JAMES ABBOTT PHOTOGRAPHY. Available at: https://jamesaphoto.co.uk/enhance-detail-and-atmosphere-with-the-orton-effect/ (Accessed: 10 June 2024).
Kolari Vision (2017) Kolari vision UV photography filter, ultraviolet bandpass transmission lens filter – kolari vision, Kolari Vision - Photography Gear & Infrared Conversions. Available at: https://kolarivision.com/product/uv-bandpass-lens-filter/ (Accessed: 04 March 2024).
Kolari Vision (2019) Kolari vision IR Chrome lens filter – kolari vision, Kolari Vision - Photography Gear & Infrared Conversions. Available at: https://kolarivision.com/product/kolari-vision-ir-chrome-lens-filter/ (Accessed: 04 March 2024).
Shainman, J. (2020) Richard Mosse ‘Artists’ Jack Shainman Gallery, Jack Shainman Gallery. Available at: https://jackshainman.com/artists/richard_mosse (Accessed: 10 June 2024).
Shea, R. (2020a) 5 Pitfalls of Infrared Photography, YouTube. Available at: https://www.youtube.com/watch?v=GPZzI6luxyA (Accessed: 19 March 2024).
Shea, R. (2020b) Diffraction in Infrared Photography, Rob Shea Photography. Available at: https://blog.robsheaphotography.com/2020/09/15/diffraction-in-infrared-photography.html (Accessed: 19 March 2024).
Shea, R. (2021) Updated Photoshop Actions for Color Infrared V3, Rob Shea Photography. Available at: https://blog.robsheaphotography.com/2021/08/07/update-photoshop-actions-color-infrared.html (Accessed: 10 February 2024).
Shea, R. (2022) Color Doesn’t Exist: A Practical Guide to Infrared Photography. First Edition v1.3.
Comentários