Black and White Panchromatic film is sensitive to visible light and records light intensity as shades of gray. Normally a Minus-Blue filter is used to eliminate the short wavelength blue light that is responsible for haze. Historically, Black and White Panchromatic film has been the most widely used.
Black and White Infrared film is sensitive to both visible and photographic infrared electromagnetic radiation and records light intensity in shades of gray. A Minus-Blue filter is used to eliminate the short wavelength blue light that is responsible for haze. This film is useful for vegetation studies because there is usually good contrast between certain plant communities, particularly coniferous versus deciduous trees. There is also good contrast at the land-water interface because of the strong absorption of infrared by water. Water in B&WIR photography appears very dark.
Color film is sensitive to visible light and records light intensity in various combinations of red, green, and blue. The large tonal range of natural colors offers an advantage to black and white films. Haze, however, can be a major problem since blue light is not eliminated with a filter. Color film is useful for such applications as coastline studies, industrial site analysis, and vegetation identification.
Color Infrared film is sensitive to both visible and photographic infrared electromagnetic radiation. It contains three emulsions that are sensitive to green, red and infrared respectively. Since all emulsions are also sensitive to ultraviolet and blue light, a Minus-Blue filter is used. The color representation in CIR is not "natural" because green light is recorded as blue, red light is recorded as green and infrared energy is recorded as red. This "color-shift," as well as high reflectance of infrared by vegetation, gives a unique and easily interpretable view of the landscape. Uses for CIR film include vegetation identification, plant stress, soil moisture, water pollution and land-cover mapping.