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Full-spectrum photography is a subset of multispectral imaging, defined among photography enthusiasts as imaging with consumer cameras the full, broad spectrum of a film or camera sensor bandwidth. In practice, specialized broadband/full-spectrum film captures visible and near infrared light, commonly referred to as the "VNIR".〔(), Definition of VNIR.〕 Modified digital cameras can detect some ultraviolet, all of the visible and much of the near infrared spectrum, as most digital imaging sensors are sensitive from about 350 nm to 1000 nm. An off-the-shelf digital camera contains an infrared hot mirror filter that blocks most of the infrared and a bit of the ultraviolet that would otherwise be detected by the sensor, narrowing the accepted range from about 400 nm to 700 nm.〔(), Spectral curves of RGB and Hot Mirror filters.〕 Replacing a hot mirror or infrared blocking filter with an infrared pass or a wide spectrally transmitting filter allows the camera to detect the wider spectrum light at greater sensitivity. Without the hot-mirror, the red, green and blue (or cyan, yellow and magenta) elements of the color filter array placed over the sensor elements pass varying amounts of ultraviolet and infrared which may be recorded in any of the red, green or blue channels depending on the particular sensor in use and on the dyes used in the Bayer filter. A converted full-spectrum camera can be used for ultraviolet photography or infrared photography with the appropriate filters. Uses of full-spectrum photography include fine art photography, geology, forensics & law enforcement, and even some claimed use in ghost hunting. == History == Full-spectrum photography has its roots in spectral imaging, both multispectral and hyperspectral imaging, which began as early as the late 1950s and early 1960s as means for geological and military remote sensing. Wideband panchromatic film has been available in various forms since the 1920s, when some UV and IR sensitivity remained in commercially available emulsions. The earliest color films sometimes included wider band color than recent commercial photographic emulsions, and can be recognized by the more reddish and or limited color tones of early color prints (not to be confused with print fading). In the late 1990s enthusiastic photographers began shooting infrared with digital cameras, necessitating either long exposures or the removal of the internal hot mirror. Most replaced the hot mirror with an infrared pass filter of the same optical thickness (to retain focus) and pass only infrared light to achieve results seen with infrared B&W film. Around 2000, electro-optical engineer David Twede, already engaged in VNIR and infrared spectral remote sensing, ventured into Full-spectrum photography art, using a modified digital camera to explore broader spectral imaging and developing an artistic style using it. Around 2003, forensics photographers using engineered cameras for specific purposes began modifying off-the-shelf digital cameras to acquire less expensive tools. Full-spectrum photography is used by enthusiasts of ghost hunting, though no claims of actually photographing psychic phenomenon with Full-spectrum or infrared photography have been substantiated. Today, there are a few places that will modify digital cameras to pass broad, full-spectrum light for full spectral imaging. A few DSLR cameras such as the Fujifilm FinePix IS Pro are purpose-designed for full spectrum use and respond from approximately 1000 nm (IR) to 380 nm (UV). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Full-spectrum photography」の詳細全文を読む スポンサード リンク
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