There are four different types of scanners:
film, hand-held, flatbed, and drum.
Film Scanners/ Slide Scanners: Film scanners
are small desktop scanners used to scan 35mm film and
slides. Slides usually are higher quality than prints and produce
a higher quality scan. Slides are brighter than prints and
have a higher dynamic range. Many slide scanners have
resolutions in the 5,000-6,000 ppi range and can be very
expensive to purchase.
Hand-held scanners: Hand-held scanners are small
instruments that you slide across the image by hand. They
can only scan 2"-5" at a time so are only useful
for small photos. They are sometimes called half-page
scanners and are the least expensive type of scanners.
Flatbed scanners: Also called desktop scanners,
flatbed scanners range from inexpensive low-end scanners
for hobby use to very high quality, expensive units used
by professionals. They generally are not as high quality
as the drum scanners
Also known as a rotary scanner, the drum scanner scans
images that are mounted on a rotating drum. The drum spins
rapidly in front of a stationary reading head on either a
horizontal or vertical unit.
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