Center for Learning and Technology, Video/Audio Systems Page 1-430 Monitors, VCR's and Projection Equipment Includes Playback and Projection and Display equipment See Televisions Monitors Scan Converters Mounting Brackets VCR s Laser Disks DVD s Video Graphics Projector Slide Projectors Video Projection Units and Mirrors Line Doublers Flat Screen Monitors Movie Projectors Overhead Projectors Portable Carts 17680 for coordination with workstation layout 17130 for coordination with interior pathways 17160 for coordination with horizontal cabling 17230 for coordination with workstation 17420 for coordination with production equipment 17660 for coordination with teleconferencing rooms 17670 for coordination with auditoriums 17800 for coordination with commodities See also: CLT17650ComputerLabsClassroomsFigures.ppt SECTION 17430 Monitors, VCR's and Projection Equipment 1.1 Televisions Televisions and VCR s or TV/VCR Combinations will be mounted on the wall in the smaller Seminar/Workrooms. Size will be 25-27 diagonal. All televisions will be 132-channel cableready, patched to the campus cable system, and include closed-captioning capability. Most functions should be available on the lower front panel without the use of remote controls. Video and audio inputs are desirable on the lower front panel as well as the rear of the set to allow patching of other devices such as other video or audio sources. Switching between cable and video will be provided via a front-panel TV button, a switch on the VCR, or an external switch. The default startup for the TV should be with the video sources rather than cable TV. Televisions should be permanently mounted with security hardware including padlocks and/or security screws used to prevent theft. From GUIDELINES & SPECIFICATIONS <http://www.classrooms.com>
Center for Learning and Technology, Video/Audio Systems Page 2 For comfortable viewing, television sets should be mounted 52" above the floor. The center of the screen will be approximately 66" from the floor. Student sight line to the TV screen will be the same as the sight line to the teacher's head in the classroom. At this height the controls are within reach. Minimize glare from ceiling lights by tilting TV down, slightly toward the floor. A 2" high wood strip, for the back of the TV receiver to rest on, provides enough tilt to avoid glare. Rule of Thumb for Viewing: No one closer than 4 times the diagonal measurement of the TV screen, nor further than 7 times. Best viewing for a 27" TV: between 9 feet and 16 feet. 1.2 Monitors Computer monitors for the instructor consoles will handle at least 1024x768 resolution and be at least 15. CRT or flat screen panels may be used and the display should be partially recessed in the instructor s console to prevent line of sight obstruction. When not in use, LCD panels should have a mechanism for storage to clear the desktop and reduce line of sight obstructions. Monitors should be permanently mounted with security hardware including padlocks and/or security screws used to prevent theft. Makes and models will be specified by PLU Computing Services and PLU Multimedia Services after consultation with the appropriate academic department. 1.3 Mounting Brackets Mounting brackets will be needed for VCR/TV units, speakers, screens, and computer projectors. All brackets will include provisions for attaching equipment with security screws and/or padlocks. TV/VCR Brackets: TV/VCR wall mounts should be rated to support 5 times the weight of the mount, TV, and VCR. Mounts should include self-contained recesses along the wall mounting plane for AC power and cable TV outlets. Makes and models of brackets will be specified by PLU Multimedia Services. For mounting instructions see: From GUIDELINES & SPECIFICATIONS: <http://www.classrooms.com> For comfortable viewing, television sets should be mounted 52" above the floor. The center of the screen will be approximately 66" from the floor. Student sight line to the TV screen will be the same as the sight line to the teacher's head in the classroom. At this height the controls are within reach. Minimize glare from ceiling lights by tilting TV down, slightly toward the floor. A 2" high wood strip, for the back of the TV receiver to rest on, provides enough tilt to avoid glare. Rule of Thumb for Viewing: No one closer than 4 times the diagonal measurement of the TV screen, nor further than 7 times. Best viewing for a 27" TV: between 9 feet and 16 feet.
Center for Learning and Technology, Video/Audio Systems Page 3 Speakers: Speakers shall be secured to wall by bracket & hardware capable of supporting 5 times the speaker weight. The typical classroom will use speakers such as JBL Control 29. Rooms 103, 105, and 207 will use EAW 5194 speakers. Makes and models of brackets will be specified by PLU Multimedia Services. Screens: Screen troughs will be recessed into the ceiling across the front of the room to accommodate changes in screen width. Screen brackets should be permanently mounted to wall studs (or to internal wood bracing if metal studs are used) with 6 angle screen brackets. Screens should be attached to brackets with short lengths of chain and S hooks at either end. The screen bottom should be typically at least 4 above the floor to reduce line-of-sight obstructions for students. See data below for various screen combinations. Screen Width 6 7 8 10 Screen Height (4:3, video) 4.5 5.25 6 7.5 Screen Height (16:9, HDTV) 3.38 3.94 4.5 5.63 Screen Bottom from Floor 4 4 4 4 Screen Top from Floor (4:3, video) 8.5 9.25 10 11.5 Closest Viewer 6 7 8 10 Farthest Viewer (8x General) 36 42 48 60 Farthest Viewer (6x Reading/Detail) 27 31.5 36 45 Farthest Viewer (4x Inspection) 18 21 24 30 See CLTComputerLabsClassroomsFigures.pdf for specific calculations and mounting instructions and CLTComputerLabsClassroomsRoomDiagrams.pdf for room diagrams. Makes and models of brackets will be specified by PLU Multimedia Services. Computer Projectors: Projector location must have provision for mounting about 2 times the screen width back into the room. The mounting position will vary with different makes/models of projectors and with the screen dimensions. The projectors will be attached with with an adjustable mounting bracket below false ceiling. The projector mounting bracket shall be secured either by unistrut & threaded rod or by replacing a ceiling tile with the mount. The ceiling tile grid must be capable of holding 5 times the weight of projector & mounting hardware and must be securely attached to mounting grid not held in by gravity alone. The projector mounting bracket shall NOT be secured by a mounting pole as the mounting position may change with future projectors. Mounting bracket as well as projector should be secured with security screws and/or locks. AC power n on the same circuit as the instructor console power should be provided in the ceiling near the projector. In addition, a network connection should be located in the ceiling near the projector. The projector should have pathways to the instructor s console via a 2 conduit on the back wall with 90 degree bend at floor/wall and stubbing out above ceiling. The conduit should have a wall-accessible J-box. Pull-lines should be included and left in the conduit. (See 17160 on horizontal cabling for specifications and details). Makes and models of brackets will be specified by PLU Multimedia Services.
Center for Learning and Technology, Video/Audio Systems Page 4 1.4 VCR s/dvd s Combination ½ VCR/DVD players will be located either in a rack in the instructor console or mounted on the wall with TV s in selected seminar/workrooms. Equipment should accommodate stereo ½ VHS and CD-R/RW compatible DVDs with NTSC Video Out and S-Video Out. Most control functions including play, pause, eject, fast-forward, fast reverse, stop, menu, and shuttle search should be available on the lower front panel so the units can be used without remote controls. Video and audio inputs/outputs are desirable on the lower front panel as well as the rear of the set to allow patching and/or pass-through of other devices. Where possible, video will be run as S-Video to the computer projector for optimal resolution. (See <http://www.conceptron.com/articles/digital_video_sources_1.html> for more detail ) Players should be permanently mounted to racks with security hardware including padlocks and/or security screws used to prevent theft. 1.5 Slide Projectors Slide projectors will be used in some rooms on an ad hoc basis. They will be locked down with security cables and locks on portable carts (including plug strip and extension cords) and will require a remote control and 25 remote control extension. Slide projectors will be Kodak Ektagraphic III series or equivalent with autofocus and 75-120mm f 3.5 zoom lens. AC power in a quad receptacle will be required in the back and front of each room centered to the middle of the screen plane. Makes and models of projectors will be specified by PLU Multimedia Services. 1.6 Computer Projection Units Projection units should be capable of at least 1024x768 resolutions at least 1500+ ANSI lumens. At least three rooms will need higher performance projectors: rooms 103 and 105 should be able to project at least 2500 ANSI lumens; room 207 should use higher-resolution projectors to cover at least 1280 x 1024 resolution. They should include 2 SXGA, 1 NSTC Video, and 1 S-Video input. Audio should be switchable by remote control. A wired remote is preferred. Network connections may be needed for some projectors for monitoring purposes. Switching between cable and video will be provided via a switch on the VCR or an external switch. The default startup for the TV should be with the video sources rather than cable TV. Audio sources will be run through the projector and looped to the amplifier and speaker to provide redundancy. Specifications include the following: LCD TFT 1024 [H] x 768 [V] minimum resolution NTSC Video: RCA (or BNC) connector 1.0 Vp-p, sync negative, 75 ohm terminated
Center for Learning and Technology, Video/Audio Systems Page 5 S-video: 4-pin Mini Din connector Y (Luminance signal) 1.0 Vp-p, sync negative, 75 ohm terminated C (Crominance signal) 1Burst.286 Vp-p, 75 ohm terminated Video Audio Input: RCA connectors (x2).5 Vrms More than 20 K ohms impedance Stereo Computer RGB Input Signal 15-pin mini D-sub connector RGB separate/composite sync/sync on green analog type input 0-0.7 Vp-p, positive 75 ohm terminated Pixel clock at least 12-230 MHz Vertical frequency at least 43-200hz Horizontal frequency at least 15-126 hz Computer Audio Input 3.5mm Stereo minijack.5 Vrms More than 20 K ohms impedance Stereo Current projector examples include Sharp PG-C30XU or XG-P10XU. Projector mounting distance from screen is likely to be about 2 time the screen width back from the front of the room. Exact mounting specifications will be available after makes and model are finalized. Makes and models of projectors will be specified by PLU Multimedia Services. 1.7 Computer Monitors Computer monitors for the instructor consoles will handle at least 1024x768 resolution and be at least 17. CRT or flat screen panels may be used and the display should be partially recessed in the instructor s console. Makes and models will be specified by PLU Multimedia Services and PLU Computing Services after consultation with the appropriate academic department. 1.8 Overhead Projectors An overhead projector or document camera will be needed for each room. Power will be provided from the interface panel in the instructor s console or from an outlet at the front of the room centered under the screen. Projectors must be secured via cable and lock onto 36 projection carts to be centered from 9 to 12 feet from the screen. From GUIDELINES & SPECIFICATIONS <http://www.classrooms.com>
Center for Learning and Technology, Video/Audio Systems Page 6 The only instructional audiovisual device designed specifically for education, is used so frequently that an overhead projector with a 14" lens is installed in each room. Faculty place overhead on a table or cart at least 9 feet in front of the screen to project an image large enough for viewing by students seated in the rear of the room. Necessary Distance between Screen and an Overhead Projector with a 14" lens for the Projected Image to Fill the Screen (using 9.5" by 7.5" transparency frame) (measured from lens to screen) an OH projector needs to be 8.6 feet away to fill a 6 foot screen (72"wide by 54"high) an OH projector needs to be 10.3 feet away to fill a 7 foot screen (84"wide by 63"high) an OH projector needs to be 11.8 feet away to fill a 8 foot screen (96"wide by 72"high) an OH projector needs to be 13.3 feet away to fill a 9 foot screen (108"wide by 81"high) an OH projector needs to be 14.8 feet away to fill a 10 foot screen (120"wide by 90"high) 1.9 Screens The average classroom is about 30 deep. Students should be seated less than a distance of 7 times screen height. 30 / 7=4.29, HDTV with a 16 x 9 ratio produces an 8 W x 4.5 H image on an 8 Screen. They should not be seated any closer that 1x the screen width. The optimal viewing cones are illustrated for each room in CLT17650ComputerLabsClassroomsFigures.pdf and CLT17650ComputerLabsClassroomsRoomDiagrams.pdf For most rooms, two screens will be mounted in the recessed screen well in the ceiling at the front of the room. Below are suggested screen sizes for each room equipped with a screen. These calculations are based on the table in Guidelines and Specifications cited below. Diagonal to farthest viewer Depth Screen First Floor Classrooms Room 103-V 105-V 114-C 115-V 124-C 125-C 131-C 132-C 108-V 107-V 180-V Wall S/E W/W East South E/E E/E E/E E/E W/W W/W North ~Depth 30 30 37 20 30 30 30 30 23 26 19 ~Diagonal 32 38 32 19 28 28 28 28 24 26 18 Screen 10 /8 8 /8 7 8 7 /7 7 /7 7 /7 7 /7 7 /7 7 /7 6 Min. Height 10 10 9.25 10 9.25 9.25 9.25 9.25 9.25 9.25 8.5
Center for Learning and Technology, Video/Audio Systems Page 7 First Floor Team Workrooms Room 121-S 122-S 126-S 128-S 129-S 133-S 134-S Wall West East East West East West East ~Depth 10 10 14 14 11 10 10 ~Diagonal 11 11 16 16 12 11 11 Screen 6 6 6 6 6 6 6 Min. Height 8.5 8.5 8.5 8.5 8.5 8.5 8.5 Second Floor Classrooms and Seminar Rooms Room 207-V 215-C 219-C 225-C 227-C 205-S Wall S/S W/W E/E E/E S/S South ~Depth 30 30 46 34 32 20 ~Diagonal 38 36 48 37 36 21 Screen 8 / 8 8 /8 10 /8 8 /8 8 /8 6 Diffusion screens? Diffusion screen? Diffusion screen? Min. Height 10 10 11.5 10 10 8.5 Third Floor Seminar Room Room 339-S Wall South ~Depth 19 ~Diagonal 22 Screen 6 Min. Height 8.5 The screen material will be matt white to provide the widest possible viewing angle (120 degrees 60 degrees off axis). A 10 wide screen provides a better viewing angle in a classroom that is wider than it is deep. Some rooms requiring higher resolution displays (207, 215, 219) may need diffusion screens. The screen handle should include a pull-chain with the end reaching slightly below the top of the whiteboard. Velcro should be attached to the top of the whiteboard and the chain to keep chain from interfering with whiteboard. From GUIDELINES & SPECIFICATIONS <http://www.classrooms.com> In most classrooms, one or two matte projection screens mounted above the chalkboard in the front of the classroom will fill video, data, slide & overhead projection needs. Matte white screens can be viewed over a wide angle, typically 120 degrees or wider. (60 degrees offcenter axis). Screens today are slightly rectangular, in a 3 units high x 4 units wide ratio. A new 30% wider ratio of 3 x 5.3 (9 x 16) for DVD and HDTV will be necessary in the future. A screen trough recessed up into the ceiling creating a pocket across the entire front of the room will permit easy screen exchange in the future as wider proportions become standard. This upcoming change in screen proportion is a reason to avoid permanent rear screen installations.
Center for Learning and Technology, Video/Audio Systems Page 8 Fit the screen to the size of the audience and the distance from the furthest seat. (See chart below) Rough rule of thumb: No one should be further from the screen than 7 times the height of the screen nor closer than 2 times the height of the screen. Mount screen high enough for the students in the back of the classroom to see the bottom of the screen, typically 4 feet above the floor. (See chart below) Multiple screens, for simultaneous projection in a classroom, provide more flexibility than one screen. Faculty projecting materials and wanting to use the chalkboard at the same time feel a large screen obstructs the chalkboard. Overhead transparencies are projected from a table in the front of the classroom, video and data from a ceiling-mounted video/data projector and slides from a table in the rear of the room. Attach Velcro to bottom of the screen cord and top of the chalkboard to prevent screen cord from hanging down the middle of the chalkboard. DETERMINING SCREEN SIZE & MOUNTING HEIGHT The depth of the room and the seating capacity determine the size of the screen installed in each room. Room Depth Seating Capacity Center of Screen to Rear Corner Seat Screen Required: less than 25' 25 Less than 30' 6 foot screen (72"w x 54"h) 25' to 30' 25-50 Between 30' and 35' 7 foot screen (84"w x 63"h) 30' to 35' 50-100 Between 35' and 40' 8 foot screen (96"w x 72"h) 35' to 40 100-150 Between 40' and 45' 9 foot screen (108"w x 81"h) 40' to 45' 150-210 Between 45' and 50 10 foot screen (120"w x 90"h) 45' to 50' 210-275 Between 50' and 55' 11 foot screen (132"w x 99"h) 50' to 55 275-400 Between 55' and 60' 12 foot screen (144"w x 108"h) 55' to 60' 400-500 Between 60' and 65' 14 foot screen (168"w x 126"h) Minimum Approx. Mounting Diagonal Height 7.5 ft. 8.5 ft. 8.75 ft. 9.25 ft. 10 ft. 10 ft. 11 ft. 10.75 ft. 12.5 ft. 11.5 ft. 14 ft. 12.5 ft. 15 ft. 13 ft. 17.5 ft. 14.5 ft. Additional Screen Considerations: For additional flexibility, add one or two screens on either side of the one center screen as sized above. Sometimes a classroom will lend itself to an additional corner screen at 45 degree angle. 1.10 Document Cameras Document cameras will be available in selected classrooms and for most videoconference-ready classrooms. Extra space in the instructor s console will be needed to accommodate these
Center for Learning and Technology, Video/Audio Systems Page 9 projectors. They shall be secured with security screws and/or cables and locks. The video camera must have at least 1024 x 768 resolution and should be usable with included toplighting. The cameras should also be adjustable with a 180 degree rotating head for use as sessionrecording video cameras. The lens should provide 16x zoom capability. Projector outputs will be sent to computer projectors via either S-Video or SVGA connections and to videoconferencing equipment via composite video. Interface to a computer should be possible via USB port. From GUIDELINES & SPECIFICATIONS http://www.classrooms.com Document cameras allow a presenter to display a 3D object, a photograph, a sheet of paper or any simple text document on a large screen using a ceiling-mounted video/data projector. A document camera does not require as much "throw" space in the front of the classroom as an overhead projector does to project a large image for students in the rear of the room to see. Some media professionals suggest using document cameras instead of overhead projectors, since document cameras are not limited to projecting only transparencies. But, the overhead projector has unique features too: It is inexpensive, simple to use, simple to maintain and since it doesn't use the ceiling-mounted video/data projector, it can be used simultaneously with computer or video images projected from the ceiling-mounted video/data projector. The document camera requires a built-in surface or a storage location in the front of the room. A drawer in the presenter's lectern can be designed to accommodate a document camera. 1.11 Portable Carts Carts will be needed for portable overhead projectors, slide projectors, etc. Carts will have 5 wheels, two of which should be lockable. Carts will include a 25 foot power cord with at least two outlets and a mechanism for storing cord. All carts should include rubber mats or carpet to cushion equipment during transport. See also 17680 for coordination with workstation layout 17130 for coordination with interior pathways 17160 for coordination with horizontal cabling 17230 for coordination with workstation 17420 for coordination with production equipment 17660 for coordination with teleconferencing rooms