Pictures are made of 405 lines ( BBCI and ITA ) . It means the electron beam scans across screen in 405 lines from top to bottom. It does this 25 times every second. It scans odd lines first, e.g. 1, 3, 5, 7, 9, 11 and so on up to 20 1/2 times. It then switchhes back to the top of the screen and covers the left out lines, i.e. 2, 4, 6, 8, 10 etc. It thus forms two interlacing frames of 20 1/2 lines each, making up the full number of 405. BBC 2 uses 625 lines, and the extra lines improve the picture quality making it smoother.
Author: Shabbir Chunawalla
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The Cathode Ray Tube ( CRT )
The gun scans the florescent screen of the TV from left to right and top to bottom ( just similar ). The tiny specks glow on for on instant. A bright speck when there are more electrons.Duller speck when there are fewer electrons. This exactly reverses what happens in the camera. TV breaks up a picture into tiny specks of light. These specks are converted into electric current.The current is in the form of electro-magnetic waves. These travel, and enter the TV to be converted back into specks of light. These specks form the original picture pattern.
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The Electron Gun
These days we are using LCD, Plasma, LED and OLED TV sets. There was a time when everybody used Cathode Ray Tube (CRT) sets. Even now many sets in rural areas are CRT sets. We shall discuss one by one the technology behind all these sets. We commence by first concentrating on CRT sets. To understand the concept of CRT, let us understand what an Electronic Gun is.
The electrical charges in the caesium dots will be released with some assistance. Each tiny charge must set up currents which could be amplified and transmitted as elecro-magnetic radio waves. This is accomplished by an electronic gun. It shoots out a beam of electrons. There are magnetic deflector coils in the muzzle of the gun. The gun can sweep the beam of electrons back and forth by its adjustment. The electron beam moves as the eyes do while reading, from left to right. This sweeping action is called scanning.
The mosaic screen is scanned fifty times every second. It releases the various electrical charges from the caesium dots while it passes over them. These charges are sent to an amplifier to make them stronger. Ultimately, they are transformed into electro-magnetic waves. These are sent across the transmission antenna.. As the charge is higher or lower on the caesium dots, the electron beam too produces a corresponding small or large electric current while scanning the dots.
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Hindi Films — Exportable or Non-Exportable
Hindi films have not become exportable except for the Indian diaspora abroad. Hong Kong films are exportable as movies are mainly action movies dubbed in English. The appeal that is physical is retained. On the other hand, Hindi films are sentimental, and highly culture specific. All characters have behavioural attributes specific to India. These movies do not appeal to the audiences outside India. Foreigners are not familiar with the greast Indian stars and singers. The classical music too communicates melancholy. That is not accepted as entertainment elsewhere. Those nusicians from India who have settled abroad are all instrumentalists who have mastered motor skills. There is no cultural barrier. The khyal vocalists have remained rooted to India. Just by working in seven films Bruce Lee is remembered even today forty years after his death, Jacky Chan’s retirement becomes news. Indian films can become exportable by being less Indian, but that makes them less acceptable here in India.
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Acting Career for Industry-related People
Many aspiring actors who happen to be the sons and daughters of industry-related people prefer to start their acting career by working as Assistant Directors (AD) before their debut. It prepares them for a full-fledged acting career. It gives them hands-on practical knowledge on the sets. It gives them a perspective of what their job constitutes later as actors. Being on the sets help them understand the film making better. Outsiders prefer the modelling route to acting. Insiders rely on the assistant director route. In future, they understand the camera angles better, minimise the reel use and economise on shooting. It gives a good insight into what is expected as an actor while facing the camera. They also become comfortable in their future career, as the environment is familiar.
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TV Camera
A TV camera converts the light and dark of an image into minute charges of electricity. A camera carries a screen or mosaic behind its lens. It contains tiny dots of photosensitive material called caesium. Though caesium dots are so close that it looks continuous, in reality the dots are separated from each other. Each dot acts as a photo-electric cell. Whenever light falls on the dots, they release electrons or small charges of electricity. When a picture is shot, the picture is focused on the mosaic screen. The caesium dots release electrons, i.e. become charged with electricity.
The number of electrons ( or the amount of electricity generated ) depends on the strength of the light falling on each caesium dot. A bright light releases more electrons and produces stronger electrical charge from each dot. A dull light releases fewer electrons and produces weaker electrical charge from each dot.
In this fashion, the lighter portion of the image being televised will release more electrons, while the darker portion will release less electrons. The variations in picture tone are translated into variations of electric charge being generated by different caesium dots. The whole picture that enters the camera resembles an identical picture made of varying electrical charges.
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TV Transmission and Reception
TV is the transmission and reception of images of moving objects by radio waves. TV starts wherever the event we wish to see occurs. It is made into a picture by the TV camera which then turns it into electricity. The electricity is changed into radio frequency power. It is sent out by a transmitter in the form of radio waves. These set up tiny electric current in the antenna on the roof. These are conducted down to the TV set. They are amplified and turned into a picture again. The whole process happen so quickly that the action at home is seen precisely at almost the same time it occurs elsewhere.
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Media Effects Theories
One assumption is that media is a stabilising force, which maintains consensus in the society and strengthens it . It assigns a role or function to media and is a ‘functionalist’ school. Here the interplay of power and conflict in the society has been ignored. The assumption is that all the forces in society compete with each other and there is free and fair play, with each group getting an equal opportunity to dominate and control. Another school of thought assumes power struggle as the pivot around which the social classes — groups revolve. Mass media may be used by the powerful as a vehicle to propagate its ideology. This is the critical school. It examines media experience in cultural and political context, media’s economics and owenership and media consumption habits.
Media effects theories have a continuum, the one extreme which puts media in all-powerful position and the other in no-effects at all position. In between, there are people who suggest that effects are negotiated by the audiences. Media effects are in fact effects of the contents on the opinions, perceptions, attitudes, beliefs and behaviour. There is research on the effects of the audio-visual media like TV and films, e.g. research on the effects of TV programmes on children. The research is mostly based pre-test and post-test methods. They could be on expected lines. The social context of media consumption was ignored.
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FrontPage — FP
A web-site is a collection of related web pages, starting with the home page and followed by other related pages through hyperlinks. The site opens at the home page. Web page is a text file in HTML which uses commands called tags to describe the page layout, and carries on-screen information and paths to other locations called hyperlinks.
FrontPage is a software developed by Microsoft to crate, publish and mange a web-site. FP allows us to type a page, add graphics to it, build tables and navigation buttons, add frames and borders, build hyperlinks and provide forms.
On completion of the design of the web page, FP writes the HTML code. It is not necessary for us to know HTML while working with FP.
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Underpayment of ( Playback ) Singers
According to conventions, the producer is supposed to pay everyone from chorus singers to musicians. However, for some practical reasons, music directors make on all-inclusive contract with the producers, and pay the singers themselves. They may under-pay singers and musicians. A new comer may even work free if he gets an opportunity to work under an established music director. Singers though underpaid make up for that with their live performances.