With infrared photography, the film or image sensor is sensitive to infrared light, which is invisible to the human eye. With film, a filter is used to let infrared (IR) light pass through to the lens but blocks all or most of the visible light spectrum (these filters look black or deep red). With a digital infrared , a filter can be used, but this results in very long exposures as most of the infrared sensitivity of digital cameras is filtered out with a high-pass filter. A more practical approach is to remove the highpass filter (which block infrared light) and replace it with an IR filter, which blocks visible light. This is the approach I have used since 2005.
Infrared Cameras/Film by Date
As my photography has evolved, I have used a number of different cameras and techniques for my infrared photography:
2009- Canon 5D MKII
2007-9 Nikon D80
2005-7 Nikon D70
2004-5 Sigma SD10
1994-2003 Kodak HIE and Konica 750