What is Infrared (IR) Photography? Have you seen these ghostly, out-of-this-world images where the trees and grass appear white or pink instead of green? Well, that’s it!
All you need is a filter that only allows infrared light to pass, blocking all the other light wavelengths. Different IR filters and/or different post-process techniques achieve interesting variations. An IR photo can be colourful or high-contrast black and white.
Any camera is capable of capturing IR photos but there is a hack that allows ‘normal’ DSLR and/or mirrorless cameras to shoot IR (or astrophotography) more efficiently. Typically, there are two internal filters, in front of the camera sensor that only allow visible light to pass. As a result, our photos, closely resemble what we see with our own eyes. What happens if we remove these filters is that the full light spectrum hits our sensor. Visible light, UV, IR, everything! This allows us to use filters, isolating the desired wavelength and shooting IR or UV or astrophotography or anything else.
Cameras where both internal filters are removed are called Full Spectrum cameras as the ones you can find on my ebay shop. When it comes to IR photography, an important practical advantage of a converted camera is that you can shoot camera handheld photos whereas to achieve similar results with a non-converted camera you need a tripod and several seconds of exposure. So for any IR photo involving moving objects and/or if we want to avoid using a tripod in every single shot, the conversion is necessary.
Below is the comparison between Hoya 720nm and Green.L infrared filters. The Hoya is perhaps the most famous IR filter. The Green.L is the first filter I purchased when I started experimenting with IR photography. I researched online shops and forums and I couldn’t find any negative comments for the Hoya. Regarding Green.L overall the comments are positive but there are a few photographers stating that it is more of a coloured glass and less of an IR filter. I decided to test them both. As I like to tinker (fix/alter/destroy/fix again) things I cut both filters to pieces! I then put the pieces in 3D printed clip enclosures, install them in a Canon 1200D camera and shoot the photos. The Hoya R72 clip filter is available to purchase here. I think that calling the Green.L a coloured glass is a bit unfair. To my eyes, both filters produce IR images. I can see though, a faint greenish tint in processed Green.L photos which resembles the results where no filter was used. My guess is that the Green.L allows a small degree of visible light to pass whereas the Hoya is purely IR. I guess this justifies the 3x Hoya filter price.
You can see the results below. The first image is a sample of unprocessed photos. The second image includes a comparison of processed photos using the same settings and post-processing.
Canon DSLR clip filters: Hoya R72 720nm vs Green.L 720nm vs No filter
Please note that IR filters are too dark to see via the viewfinder. Using Live View is the recommended workaround.
