d. You will probably come across many types of portable cameras. The
big difference among the various models is picture quality and degree of
automation. There are currently four types of ENG cameras; the three-tube
(three-gun) camera, the single-tube (single-gun), the charge-couple device
(CCD) camera, and the camera-recorder unit. The two-tube camera is almost
obsolete.
e. The high quality three-tube portable camera works on the same
principle as the three-tube studio camera, except it contains the smaller
2/3-inch or 1/2-inch camera pickup tubes. Its internal optical system can
either be dichroic mirrors or prism block. The latter is preferred, because
it makes the camera more sensitive to light and less sensitive to physical
shock.
f. The single-tube camera contains a single 1/2-inch, 2/3-inch, or 25mm
tube with a stripe filter as color separator device. It is usually smaller
and lighter than the three-tube camera, but its pictures are of lesser
quality.
g. The smallest camera is the one using a CCD as the imaging device.
Although such "solid state" cameras have many advantages over the
conventional camera with pickup tubes as the imaging device, (small size,
long life, no lag), the relatively low resolution of the chip has so far
prevented the CCD camera from replacing the heavier and more sensitive
pickup tube camera.
h. The camera-recorder unit is a hybrid of an ENG/EFP camera and mini-
recorder that attaches directly onto the back of the camera.
This unit,
which is slightly heavier than a three-tube camera, rests on your shoulder.
There is no need for additional VRs dangling from your shoulder or for
cables to connect your camera with the VR. This camera-recorder combination
comes close to the traditional news film camera in weight and operation.
The news film camera generally uses a single 1/2-inch Plumbicon or Saticon
tube and has all the automatic features of the three-tube ENG/EFP cameras.
The camera and VR can be separated and used independently.
6.
Parts of the camera.
The standard TV camera consists of three main
parts which are the lens, the camera body itself, and the viewfinder.
a. The lens selects a certain field of view and produces a small
optical image of this view.
The lens and certain attachments to it are
sometimes called the external optical system.
b. The camera body includes camera pickup tube(s) or a solid state
imaging device and the internal optical system which consists of a series of
mirrors or prisms.
c. Viewfinders are an intricate part of the camera and are designed for
operator use for framing, focusing, and automatic messages displayed on the
screen. The viewfinder is about 1.5 inches in size.
d. The camera, the combination of lens, pickup device and internal
optical system, and the viewfinder, is called the camera head because it is
at
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