Two Main Types of Scanners
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The digital revolution has had far-reaching effects on many fields, not the least of which are photography and image-making. Digital scanners turn photos and documents into files that users can share through e-mail or edit in a digital environment with specialised software.
Choosing the right type of scanner is a matter of knowing what the task requires and how each type of machine operates.
Flatbed scanners are among the most common and affordable digital scanners on the market. They feature a flat pane of glass on which the user places a photograph, document or book. Beneath the glass, the scanner includes a light to illuminate the document and a digital sensor to photograph the document in great detail.
Most flatbed scanners include adjustable settings via software that allow users to make quick, low-quality scans or more detailed scans that take longer to produce and result in larger digital files. Some flatbed scanners also include scanning elements on both the glass surface and the underside of the lid, allowing them to scan both sides of a double-sided document at the same time.
Photo scanners are part of a class of speciality scanners that create digital copies of printed photographs. While a flatbed scanner will scan a photograph, photo scanners are built especially for this task. The devices usually employ a sheet-fed system with a slot into which the user inserts a photo. Sheet-fed photo scanners are fast and produce very high-quality images for digital editing or archiving.
Drum scanners are another option popular with photo and publishing professionals. The devices use a rotating drum that holds the photo in place and spins it past a stationary sensor. Drum photo scanners are expensive but they can produce images suitable for printing in magazines or on billboards.
Beyond flatbed and photo scanners, there are several options for producing a digital version of an image or document. Handheld scanners were a popular option before flatbed scanners became affordable and readily available. Handheld scanners use a sensor on the end of a wand, which the user drags over the surface of a document to scan text or images. Handheld scanners produce lower-quality images, but are more portable than flatbed scanners.
Negative scanners are another specialised option for photographers. The devices use a special, powerful sensor to scan a film camera negative. Negative scanners are not useful for scanning anything else, making them more of a specialised tool for professionals who need to duplicate and archive work shot on film.