February 13, 2008
Infrared Photography is based on capturing light in the 700-900nm section of the light spectrum. We normally perceive it as heat, but with certain filters it is possible to capture this in a photo. However most digital cameras have IR filters to prevent oversaturation in the red channel. Canon Digital SLRs have quite a strong filter, but you can still capture photos by using long exposures. Other cameras have weaker filters and are more suited to Infrared. In fact, there is a whole industry based around removing the IR filter from a camera, specifically for IR photograpy. Like I said you can still shot with longer exposures to compensate for the filter. The other gotcha with Infrared is that due to chromatic aberration in most lens, the IR focus point is not the same as that of the visible light spectrum. Most primes have a little red dot showing this point. Lenses like the Canon 24-70L have a red line indicating the focus point at different focal lengths. I’ve used a Hoya R72 filter on the Canon 28mm f2.8 lens. I do have the Cokin IR filter to try, and will get to shooting with it when the weather improves!
Unprocessed IR shots (especially from a filter like the Hoya R72) tend to look red in colour. False Colour IR photos are normally created by swapping the Red and Blue channels in Photoshop. Lightroom has no way of doing this, so we can only hope to emulate false colour IR. I’ve published some IR presets over at Inside Lightroom in the past, and today I’m going to give you a few more basic ones to work with. These were created with the Hoya R72 in mind, but should give a start point for other filter types. The basis for these involved dropping the WB slider to make it bluer, but ended up using Split tone for colour, mixed with a reduction of Vibrance. Mostly it was trial and error.
To install these, open the Zip file and place the folder into the Develop Presets folder. To access this folder, Right Click on a Develop Preset in the Left Panel and choose Show in Finder/Explorer.
For a great reference on Digital infrared, check out this article written by fellow Lightroom tester David Burren.
Please feel free to leave comments on these. I don’t think it will be possible to achieve the same quality as a colour swap, but I’m interested in hearing how people get on!