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Noun of supervisory system foundation explains
From;    Author:Stand originally
Video of perpendicular synchronism, color is compound signal synchronism, outside lock of line of synchronous, dc is decided and complete synchronism is the synchronous method that differs between camera. The method that if complete synchronism is best between broadcast studio camera,completely synchronous collectivity is locked up is two application that are used at nicety surely. It will be synchronous: Level, perpendicular, even / odd area, colour sparks frequency and phase.
Perpendicular synchronism is the simplest method comes synchronous two camera, will make sure video can use vintage switch through perpendicular drive frequency period or 4 break up a machine, in same a few video causes show on monitor. Perpendicular drive signal normally by repeat frequency 20/16.7 millisecond (50/60 hertz) the pulse composition with width of pulse 1~3 millisecond.
Chromatic video is compound video of compound signal delegate and color touch video of signal synchronism color signal, mean camera to be able to be mixed external signal of compound color video is synchronous. However although call chromatic video compound signal synchronism, undertake horizontal synchronism and perpendicular synchronism only actually, and spark without colour synchronous.
Outside synchronous and special be similar to chromatic video compound signal is synchronous. A camera can synchronous the video signal at another camera, outside the chromatic video that synchronous camera can use an input is compound signal, extraction level and perpendicular and synchronous signal will do synchronism. When video camera uses processor of mark of question of number of colorless scroll   to fall in fluorescent lamp, what can produce serious lubricious roll only is video. Video meeting becomes blue, pink farewell to arrive from white change white, circulate so. Because alternating current source moves in the problem that 50/60 hertz place poses,this is. White-hot bulb can provide stable light, and the light of fluorescent lamp because the intensity of alternating current and colour fluctuate in commutation with the speed of 8.3ms. Traditional camera computation gives white balance to need 100~150ms (0.1~0.15) , slower than alternating current 8.5ms, because this can never be caught up with. Right current and video be clear that through ability of 8 total cycle time landed add lustre to rolls. Be in a poor light compensation   is in a poor light compensation can offer the ideal exposure in award of the honor before line of very strong bias light compensation, no matter main goal moves,arrive among, be controlled up and down or the either position of screen. One does not have the common camera that exceeds strong dynamic characteristic to be like the choice of the aperture of the shutter speed of 1/60 second and F2.0 only, however the very bright setting at the back of a main goal or a point light source are inevitable, camera decides the average that gains all and latter light the grade of exposure, this is not a good method, when because become,shutter rate increases, aperture can be shut to bring about main goal becomes too black and be not seen. To overcome this problem, one kind calls the area theory that is in a poor light compensatory method counterpoises through adding to be used extensively to be on most camera. Video be broken up 7 above all or 6 area (two area are reduplicative) , every area can add grade of authority computation exposure independently, for example intermediate part can add the others 9 times of area piece, because this one is among the picture,positional target can be seen very clearly, because exposure basically is,consult the radial grade of the area intermediate has consideration. Have a very big drawback however, if main goal from which idle shift controls the seat to the fluctuation of the picture, the target can become very black, because it is not opened by distinction now,will had been not added to counterpoise.
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