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A high-speed camera is a device capable of image exposures in excess of 1/1,000 or frame rates in excess of 250 frames per second.〔Journal Of The Society Of Motion Picture Engineers: High-Speed Photography, Preface p.5, Mar 1949〕 It is used for recording fast-moving objects as a photographic image(s) onto a storage medium. After recording, the images stored on the medium can be played back in slow-motion. Early high-speed cameras used film to record the high-speed events, but today high-speed cameras are entirely electronic using either a charge-coupled device (CCD) or a CMOS active pixel sensor, recording typically over 1,000 frames per second into DRAM and playing images back slowly to study the motion for scientific study of transient phenomena.〔(High Frame Rate Electronic Imaging )〕 A high-speed camera can be classified as: # A high-speed film camera which records to film, # A high-speed video camera which records to electronic memory, # A high-speed framing camera which records a short burst of high frame rate images to film or a network of CCD cameras, # A high-speed streak camera which records a series of line-sized images to film or electronic memory. A normal motion picture film is played back at 24 frames per second, while television uses 25 frames/s (PAL) or 29.97 frames/s (NTSC). High-speed film cameras can film up to a quarter of a million frames per second by running the film over a rotating prism or mirror instead of using a shutter, thus reducing the need for stopping and starting the film behind a shutter which would tear the film stock at such speeds. Using this technique one can stretch one second to more than ten minutes of playback time (super slow motion). High-speed video cameras are widely used for scientific research,〔scientific research 〕〔scientific research〕 military test and evaluation, and industry.〔(【引用サイトリンク】url= http://www.qualitymag.com/Articles/Industry_Headlines/BNP_GUID_9-5-2006_A_10000000000000241598 )〕 Examples of industrial applications are filming a manufacturing line to better tune the machine, or in the car industry the crash testing to better document the crash and what happens to the automobile and passengers during a crash. Today, the digital high-speed camera has replaced the film camera used for Vehicle Impact Testing.〔(Replacing 16 mm Film Cameras with High Definition Digital Cameras )〕 Television series such as ''MythBusters'' and ''Time Warp'' often use high-speed cameras to show their tests in slow motion. Saving the recorded high-speed images can be time consuming because the newest consumer cameras today have resolutions up to four megapixels at record rates over 1000 frames per second, which means in one second the user will have over 11 gigabytes of image data. Technologically these cameras are very advanced, yet saving images requires use of slower standard video-computer interfaces.〔(REVIEW: High Speed Cameras, Jan. 4, 2011 )〕 While recording is very fast, saving images is considerably slower. One of the solutions to drive down the recorded data, or to minimize the required time to look at the images, is to pre-select only the parts which are interesting enough to film. During industrial breakdown analysis, cyclical filming focuses only on that part of the cycle which is interesting. A problem for high-speed cameras is the needed exposure for the film, so one needs very bright light to be able to film at forty thousand frames per second sometimes leading to the subject of examination being destroyed because of the heat of the lighting. Monochromatic filming (black/white) is sometimes used to reduce the required amount of light. Even higher speed imaging is possible using specialized electronic charge-coupled device (CCD) imaging systems which can achieve speeds of up to or in excess of 25 million frames per second. All development in high-speed cameras is now focused on digital video cameras which have many operational and cost benefits over film cameras. Recent advances in the form of image converter devices are able to provide temporal resolutions of less than fifty picoseconds, equivalent to over 20 billion frames per second. These instruments operate by converting the incident light (consisting of photons) into a stream of electrons which are then deflected onto a photoanode, back into photons, which can then be recorded onto either film or CCD. ==Uses in television== *The show ''Mythbusters'' prominently uses high-speed cameras for measuring speed or height. *''Time Warp'' was centered around the use of high-speed cameras to slow things down that are usually too fast to see with the naked eye. *High-speed cameras are frequently used in television productions of many major sporting events for slow motion instant replays when normal slow motion is not slow enough, such as international Cricket matches.〔(【引用サイトリンク】 title=NAC High Speed Cameras Are Popular Choices for European Broadcasting )〕 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「High-speed camera」の詳細全文を読む スポンサード リンク
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