BANDWIDTH
[Film Technology]
[Film Technology]
This might be quoted as ±3dB
50HZ to 12KHZ. 50HZ is the lowest frequency
reproduced while 12KHZ is the highest. The ±3dB is simply a way of the limits over which
the amplitude changes . ±dB or 6dB being a ratio of 2:1. The range of
frequencies encompassed by an electronic system transmitting television pictures (video),
or sound signals(audio signal). A
video system must be capable of handling a wide
frequency range [wide bandwidth] if it is
to transmit pictures with fine detail. Loss of high frequencies gives a blurred
picture while a full bandwidth gives sharp crisp outline. Video frequency extended to 5.5 MHz for broadcasting standard 625 line colour signals. The colour information
or chrominance needs a bandwidth of only 1MHZ,
because human perception of colour details is limited. For CCTV may extend only t0 2.5 MHz with the colour information reduced to 0.5MHZ. The effect of
reducing bandwidth is to reduce detail in the picture.
e-mail : pratheepvasudev@gmail.com
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