THROUGH A LENS261The first CCTV (closed-
circuit television) camera that
was installed in the UK was in- It was put in Guy’s
Hospital, London, United
Kingdom. There are
approximately 20 million
CCTV cameras in
the world.
7
/^7
1920s
Small cameras with
interchangeable lenses
were developed in the 1920s.
This allowed photographers
to take a wider range
of photographs.
1970s
Cameras were made with
automatic exposure and
electronic autofocus in the 1970s.1990s
The technology for digital
cameras was invented in the
1970s and it was developed in
the 1980s, but it wasn’t until
the 1990s that digital cameras
came into popular use.Movie cameras are similar to still-
image cameras except that the film
runs continually. Each frame of film
captures a slightly different image so
that when the frames are run back
through a projector you get the
illusion of continuous movement.
Movie cameras can also record sound
at the same time.Video cameras and camcorders
These initially used analogue and
then digital tape to record and store
information. Now they use optical
disks or memory cards. Camcorders
are mainly used for home movies.
Over the years they have become
smaller and lighter and can be
carried in one hand.Professional studio cameras are
used in television. They split the light
into red, green, and blue and detect
each color separately, which gives a
better quality image. The pictures are
sent to a separate recorder. Most
studio cameras are mounted on
special carts, but they can also be
attached to moving vehicles. INSTANT PRINTS
Polaroid cameras take pictures that
develop themselves, producing a photo
a minute or so after
it has been taken.TECHNOLOGYFACT FILE
Light needs to
travel through the
lens in order to
capture an image.Filters control the
light coming
through the lens.Lenses can be changed over to obtain a required
effect. Wide angle lenses, as the name suggests,
are used to take wide shots.(c) 2012 Dorling Kindersley. All Rights Reserved.(c) 2012 Dorling Kindersley. All Rights Reserved.