Camera :
An electronic
device which converts light into an electrical signal.
There are Black
/ White and colour cameras.
CCD = Charge
Couple Device chip. This chip has thousands of pixels.
Each pixel represents a point of light. The intensity
of light falling on any pixel is proportional to the
voltage it generates. Thus the brighter the pixel, the
higher the voltage. The chip comes in 1/3”, 1/2” etc
formats.
Lens:
Focuses the
light from a scene onto the CCD chip.
In choosing
a lens, you must consider :
- focal length
- camera format
- F stop and
depth of field
- Iris type
- CS or C mount
Focal Length :
The distance
between the lens and the point of focus. Its measured
in mm.
Short focal
length = gives wide angles of view.
Long focal
length = gives narrow angles of view.
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