A film scanner is a device made for scanning photographic film directly into a computer without the use of any intermediate printmaking. Historical precedent Scanners can be considered the successors of early telephotography input devices consisting of a rotating drum with a single Photodetector at SCAN or Schedules for Clinical Assessment in Neuropsychiatry is a set of tools created by WHO aimed at diagnosing and measuring Mental This article is mainly concerned with Still photography film For Motion picture film please see Film stock. They provide several benefits over using a flatbed scanner to scan in a print of any size — the photographer has direct control over cropping and aspect ratio from the original unmolested image on film, and many film scanners come with specialized software or hardware designed to remove scratches, film grain, and improve color reproduction from old negatives. Historical precedent Scanners can be considered the successors of early telephotography input devices consisting of a rotating drum with a single Photodetector at A photographer is a person who takes a Photograph using a Camera. Hardware is a general term that refers to the physical artifacts of a Technology. Film grain or granularity is the random optical texture of processed Photographic film due to the presence of small grains of a metallic silver developed from In photography a negative may refer to three different things although they are all related
Film scanners can accept either strips of 35 mm or 120 film, or individual slides. 35 mm film is the basic Film gauge most commonly used for both still Photography and Motion pictures, and remains relatively unchanged since its In Photography, a reversal film is a still positive image created on a transparent base using photochemical means Low-end scanners typically only take 35mm film strips, while medium- and high-end film scanners often have interchangeable film loaders. This allows the one scanning platform to be used for different sizes and packaging. For example, some allow microscope slides to be loaded for scanning, while mechanised slide loaders allow many individual slides to be batch scanned unattended. A microscope slide was originally a 'slider' made of ivory or bone containing specimens held between disks of transparent mica
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Dust and scratches
Dust and scratches on the film can be a big problem for scanning. Because of their reduced size (compared to prints) the scanners are capable of resolutions much higher than a regular flatbed scanner; typically at least 2000 samples per inch (spi), up to 4000 spi or more. At these resolutions dust and scratches take on gigantic proportions. Even small specks of dust, invisible to the naked eye, can obscure a cluster of several pixels. For this reason, techniques have been developed to remove their appearance from a scan, see film restoration. The film preservation, or film restoration, movement is an ongoing project among film historians archivists Museums and Non-profit organizations to rescue
The simplest is the median filter, often called despeckle in many graphic manipulation programs, e. In Image processing it is usually necessary to perform high degree of Noise reduction in an image before performing higher-level processing steps such as Edge detection g. in Adobe Photoshop and the GIMP. The GNU Image Manipulation Program, or GIMP, is a free Raster graphics editor used to process digital graphics and photographs It works by examining a pixel in relation to the pixels surrounding it; if it is too different from the surrounding pixels then it is replaced with one set to their median value. In Probability theory and Statistics, a median is described as the number separating the higher half of a sample a population or a Probability distribution This and other methods can be quite effective, but have the disadvantage that the filter cannot know what actually is dust or noise. It will also obliterate fine detail in the scan.
Infrared cleaning
Infrared cleaning works by collecting an infrared channel from the scan at the same time as the visible colour channels (red, green, and blue). Infrared cleaning is a technique used by some Film scanners and Flatbed scanners to reduce or remove the effect of dust and scratches upon the finished scan Infrared ( IR) radiation is Electromagnetic radiation whose Wavelength is longer than that of Visible light, but shorter than that of This is done by using a light source that also produces infrared radiation, and having a fourth row of sensors on the linear CCD sensor. A charge-coupled device ( CCD) is an analog Shift register, that enables the transportation of analog signals (electric charges through successive stages (capacitors Photographic film is mostly transparent to infrared radiation (no matter what the visible image contains) but dust and scratches aren't, so they show up in the IR channel. This information can then be used to automatically remove the appearance of dust and scratches in the visible channels and replace them with something similar to their surroundings. A major limitation of this technique is that it can only be used on dye-based (color and chromogenic black-and-white) films; the image-forming silver particles in most black-and-white film stocks are opaque to infrared radiation.
Scanner manufacturers usually have their own name attached to this technique. Kodak developed Digital ICE at their Austin development centre, and is licensed by Epson, Nikon, Microtek and some others. Eastman Kodak Company ( is an American multinational Public company which produces imaging and photographic materials and equipment Digital Image Correction and Enhancement is a set of technologies related to producing an altered image in a variety of frequency spectra or Epson, is a Japanese company and one of the world's largest manufacturers of inkjet, dot matrix and Laser printers scanners ( also known as Nikon or Nikon Corp, is a Multinational corporation headquartered in Tokyo Japan specializing in Optics Microtek International Inc is a Taiwan -based manufacturer of Digital imaging products and other Consumer Electronics. Canon developed its own FARE (Film Automatic Retouching and Enhancement) system. is a Japanese Multinational corporation that specializes in imaging and optical products including Cameras photocopiers and Computer printers
See also
External links
Historical precedent Scanners can be considered the successors of early telephotography input devices consisting of a rotating drum with a single Photodetector at A motion picture film scanner is a device used in Digital Filmmaking to scan original film for storage as high-resolution Digital intermediateDapyx Software network: MP3 Explorer | Ebook Manager | Zenithic