Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version VT1.00C 11/1/84; site vortex.UUCP Path: utzoo!watmath!clyde!cbosgd!ihnp4!ucbvax!decvax!bellcore!vortex!lauren From: lauren@vortex.UUCP (Lauren Weinstein) Newsgroups: net.video Subject: Re: Gen Lock Message-ID: <813@vortex.UUCP> Date: Wed, 25-Sep-85 15:02:21 EDT Article-I.D.: vortex.813 Posted: Wed Sep 25 15:02:21 1985 Date-Received: Sun, 29-Sep-85 05:14:11 EDT References: <3475@utah-cs.UUCP> Organization: Vortex Technology, Los Angeles Lines: 23 Very briefly, genlock refers to all video sources running off a common horizontal and vertical (or composite) sync source. In a studio, there is normally a master sync generator for all air-related equipment-- VTRs, cameras, switchers, etc. To do smooth switching, effects, or virtually anything else, you gotta be locked onto a common sync. If a graphics board says it will lock onto external sync, then you can in theory do things like superimpose or key insert graphics onto an external video source. However, there are several things to watch out for: 1) Many boards that claim to have this capability do it badly, resulting in poor supers or insert keying. 2) Many consumer VCRs have pretty crummy sync stability. Graphics "jitter" may result if such machines are used. 3) If you want to have color graphics interact with an external COLOR signal, the circuitry involved is considerably more complex. . Many boards can't handle it. You have to lock onto the colorburst phase of the external signal to keep the board's color signals and the external signal in phase. --Lauren-- Brought to you by Super Global Mega Corp .com