The human eye can see light and its reflected colours of a limited range. Generally, we call this the visible light spectrum, and this light has wavelengths from 380nm to 750nm. Beyond this range, that is, wavelengths below 380nm (ultraviolet) and above 750nm (infrared), the light is invisible to humans. Some insects and animals can see beyond the visible light spectrum.
Infrared (IR) photography is the formation of images with light at wavelengths above 750nm. In reality, most IR photography is actually the capture of near-infrared (NIR) light of wavelengths up to 1300nm, or in simpler words, the lower end of the infrared range. However, most people simply use the term “IR” or “infrared”.
Near-infrared photography can be done using most digital cameras. The CCD/CMOS imagers in most digital cameras can “see” near-infrared (NIR) light, but it is blocked away by an IR-block filter. This IR-block filter is often a clear or bluish-tint glass fitted on top of the imager.
For simplicity in explanation, generally NIR images can be photographed with a digital camera using an IR-pass filter attached in front of the lens. It is much better if the IR-block filter inside the camera is removed and an IR-pass filter is fitted on top of the imager, but this requires dismantling the camera.
Dismantling to repair or modify a digital camera should only be done by a qualified, trained and experienced technician. Electric shock, personal injury and damage can occur if a camera is dismantled by an unqualified person.
Although my interest in photography is primarily in portraits, I also have some interest in infrared photography. At my workplace in Camera Clinic, I have converted a few digital cameras to do infrared photography.
Some of the digital cameras I have converted for infrared include:
Nikon D1, D70, D200
Nikon CoolPix 5700
Canon EOS 10D, EOS 20D
Canon PowerShot G10, PowerShot SX100IS
The following gallery presents infrared images I photographed in 2007 and 2009. These images have been appropriately enhanced in Adobe Photoshop for an improved visual appearance.
The Nikon D50, Nikon CoolPix 5700 and Fuji FinePix S20 Pro used to shoot the above images were modified at my workplace Camera Clinic.