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VIDEO Use in the classroom Operation Set up Filming Technical Information       - world standards       - cassette systems Video Discs INTRODUCTION The classic way of using a video program in the classroom is left over from the years of film. Since a film projector was difficult to start and stop, or cue up to one or more points on the film during the class session, it was usually started at the beginning and let to run to the end. In other words, the film took over control the class from the teacher for the entire time it was running. It was difficult for the teacher to emphasize different features within the film at the time it was being presented, thus loosing much of the importance of the specifics as they occurred in the film. This could only partially be made up in summarizing and reviewing, after the film. PROPER USE IN THE CLASSROOM With video, the presentation can be, and should be kept, in the teacher's control. The instructor can stop the program to emphasize a point and discuss it. The instructor can jump to the points that are important and avoid points that are not. The instructor can lower the sound, allowing direct teaching while using the video picture for graphic information only. If a DVD machine is used, the instructor simply has to select the scene or position number, and the film will immediate begin at the point chosen. Some DVD players or DVD computer programs allow to preprogram a list of beginning and end points, so the instructor need not have to worry about pushing many extra buttons during the class. With a video cassette machine, one has to wait until the cassette gets to the prescribed position. On most machines, this means having to stop it manually at exactly the right number, which, of course, takes time and one can miss the intended point on the cassette. [It is advantageous to edit the cassette prior to using it in class, but with normal VHS machines, there is a great drop in the quality of both audio and video in each generation of copies. Many professional films have a "shield" which causes distortions in picture and/or sound when copied.] In all cases, proper didactic use of video requires preparation. One should not decide at the last minute to show a film if one wants to use the film and class time efficiently. My particular feeling is that any segment more than ten minutes, detracts from effective teaching, taking control of the class from the teacher. Segments of 2-5 minutes are optimal. When the viewing a complete film is deemed necessary, it should be viewed as an out of class assignment and using class time for review and discussion, as necessary. OPERATING THE VIDEO CASSETTE RECORDER (VCR) The arrow on the videocassette shows the direction in which the cassette should be placed into the VCR. To operate: There is an on/off switch. In many VCRs, this switch is automatically turned to "on" when a cassette is place into the machine. The play or "forward" button runs the machine/film. [On some machines, pressing this button twice will run the cassette at double the normal speed. The film on the screen will seem a little fast and there will be (in most cases) no sound. Push the "play" one more time to return to regular speed.] The stop bottom brings the cassette to a hault. The fast forward button allows the forward running of the cassette at a high speed, without picture. On many VCR pushing or holding (depending on the machine) this while the machine is in the "play" mode, will run the picture at a fast speed forward (forward search mode). The rewind button is to run the cassette in the reverse direction. Using it while the VCR is in the "play" mode on most machines allows for viewing the cassette in reverse (reverse search mode). The pause button allows the stopping of the cassette with the picture on the screen. (A VCR that has four heads will show a stable "frozen" picture; on a machine with two heads, the picture will jump.) MACHINE SET UP The basic video playback system entails a video or DVD machine and a monitor (screen, television). All of today's screens/monitors have direct audio and video inputs to be connected to the video or DVD machine. Most video machines can also be connect via the antennae socket on the monitor and tuned to the specific channel (RF frequency) that the video machine's internal adaptor emits. DIRECT HOOK UP The video out socket of the VCR or DVD should be connected to the video in of the monitor/screen/television; the audio out of the VCR to the audio in of the monitor. Connectors/Cables: The most commonly used connectors are RCA (or phono) plugs. The scart or Europin is a rectangular shaped multi-pin connector which contains many functions (video in/out, audio in/out/stereo, etc.). The video BNC pin is used on the more professional machines. Multi-function mini pin, both audio and video contained in a mini pin is used in many camcorders. S-video pin, a four pin connector is used for higher quality "S" video. One must determine which connectors are need for the specific VCR and monitor and used the cable connection with the proper pins, and adaptors, if needed, to connect the two machines. Connect the two machines using the proper cable/connectors. Set the monitor to the channel, or the proper "input selection" as prescribed by the monitor's operator's manual. RF HOOKUP [Most VCRs have an internal converter to change the audio and video signals to the frequency of a television station (usually between channels 32-40, UHF).] Attach an antennae cable to the television and to the "antenna out" of the VCR. Run a good videocassette with sound and picture in the VCR. Check in the operator's manual of the television set how to set a channel; search for, or manually set the channel. When the program of the cassette running on the VCR appears on the screen, set FILMING FOR CLASSROOM USE Easy video filming allows the teacher to bring outside or real-life illustrations/ observations into the classroom that may otherwise not be available or require a field trip. Film only the information necessary for the classroom. If the filming is not going to be edited prior to classroom use, plan exactly what is to be filmed, for how long, and in which order. Film exactly according to this script. Don't attempt a dramatic production (unless it is part of the objective for filming). It usually turns out foolish and time wasting in the classroom. Use sound only when needed. In most cases, the instructor should give the explanation live in the classroom and not from the filming. [While filming, it is often good practice to voice explanations of what is being filmed for classroom preparation. The sound should be turned off when the lesson is being given.] TIPS ON FILMING Move the camera/picture with a reason, not just because there is nothing else to do. The iris is usually automatic. Major contrasts of light could darken, or even black out the picture you are trying to shoot. When inside, be careful not to shoot toward a window or open door. The iris closes down for the brightest light it detects and anything less bright is darkened. Frame the picture in a manner that is pleasant for viewing. Persons in the picture should be looking into the frame, not out of it; leave space in the direction the person is looking. (For example, if the person is looking directly into the camera, center the image. If he is looking right, place him on the left of the frame looking into blank space on the right of the frame.) Attempt to put only necessary information into the picture. Non-essential information is disturbing to the viewer and takes his mind off what is being emphasized. In following a moving object, have the camera lead it, not trail it. TECHNICAL INFORMATION INTERNATIONAL STANDARDS There are three systems of video used in the world, all incompatible: PAL           Europe NTSC       North America, Japan SECAM     France, former Soviet Union, many Middle Eastern countries are using a different form of SECAM Until a few years ago, most of Eastern Europe was on the SECAM system; by now, almost all have converted to PAL. Some of the former Soviet Union are also switching. Israel uses the PAL system. Many of our VCRs are equipped with NTSC playback capability because we received many tapes from North American. The opposite is not true. A cassette taped in Israel usually cannot be seen at all in the US or Canada. VIDEO CASSETTE SYSTEMS VHS Most home video cassette systems today are the VHS standard. Some video cameras (JVC and Panasonic) use this system. Their minicassettes fit into an adaptor and will play in a standard VHS machine. VIDEO 8 Most home cameras use the Video 8 system. All video cameras can be used as a playback unit, and while Video 8 cameras can be directly hooked to a monitor for viewing, they cannot be played on a standard VHS machine. The can, however, be transferred to a VHS tape by connecting the camera to the VCR (see camera's instruction manual). Then, playback the tape on the camera and record on the VCR. DV Digital Video cameras today cost over twice the price of the others but film a much better quality picture. They can also come in much smaller models than the other systems, and can me controlled by a computer for editing purposes. VIDEO DISCS DVD The DVD system has been internationally set as the basic standard for video and audio playback and recording and computer ROM and removable RAM. It has become very successful as a video playback format, but complications and nonstandardization of recording (video and computer) and audio have delayed the DVD standard from becoming the all encompassing format that had been hoped. CD-VIDEO A lesser quality video format used on regular computer CD discs, mostly for computer playback. Ó 2005 Steven F. Rosenberg