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l behind a presenter and next to a projection screen.Don39。t offered as a standard, it does contain prehensive criteria that can be used as pass/fail parisons for videoconferencing lighting applications. IESNA hopes that the new guide will provide lighting, AV, architectural, and electrical designers with a mon basis for videoconferencing room lighting design.SEEING THE DIFFERENCE In the early days of videoconferencing, users were often just happy to have a picture that was being transmitted hundreds or thousands of miles. It wasn39。 Be sure that back and side walls are evenly lit at about the same level as the participants (this may need to vary depending on how light or dark the finish color is). Use large, directional luminaires for key lighting where possible to reduce glare for the participants. Spot fixtures may be required for presenters next to projected displays. s councils for both InfoComm International and NSCA. Contact him at 6 / 6。 Provide zoned, dimmable lighting control with an AV system interface. Put any decorative light fixtures on a separate zone so that they can be turned off during a videoconference. Tim Cape is a contributing editor for Pro AV, the principal consultant for Atlantabased technology consulting firm Technitect LLC, and coauthor of “AV Best Practices,” published by InfoComm International. He39。 Select a table finish that39。 Consider both key and fill light sources. The key light should be in the 400 to 500 lux range when measured with a vertically oriented light meter. s important to consider the type of display being used in the videoconferencing environment. While a directview display such as a CRT, plasma, or LCD monitor is very tolerant of light, front and rear projected displays require more attention to luminaire selection and overall lighting design. Many lighting designers are using indirect lighting approaches that work well for typical conference rooms, classrooms, and open offices without projected displays. However, this can be problematic when projected displays are to be used in a videoconferencing environment because the relatively uncontrolled light in these designs may put too much light on the display when light levels are set for camera useThe solution here is to limit the use of indirect lighting when projected displays are involved, using more controlled, louvered fixtures instead. Point source downlighting and track lights should be a last resort for primary participant lighting.Other important issues There39。s important to use larger surface luminaires such as 1 by 4foot or 2 by 4foot fixtures where possible to reduce the potential for glare that can acpany point source fixtures such as track lighting.Though fill light can e from the ceiling, more often we depend on the table surface to provide fill light on facial features, so the table surface at the participant39。s limited dynamic range.Background light is the light that covers the background in the camera39。s useful to note that exact conversions should be used when reporting measurements, but when both are given as criteria a simple conversion factor of 10 is often used instead of .Luminance is the luminou