Cameras - Polycom HDX 9006 Integrator's Manual

Integrator's Reference Manual for Polycom HDX Systems Room Design and Layout
videoconference cameras can no longer operate, since they require even, bright, color-corrected light. A
direct conflict between these two technologies is clear. In the event that a rear projection room cannot be
set aside, retro-projection units can be purchased from a number of manufacturers. These units normally
are available in sizes ranging from 40" to 72" diagonal measure. To display high-quality video while
maintaining optimum lighting for interactive video meetings will require a projector of the "light-valve" or
DLP™ class.
Regardless of the exact type of projector selected and the exact nature of "front versus rear," there are
certain essential rules for projector placement. The goal in projection is to get the image beam to aim directly
into the audience's eyes. In Western cultures the average distance from the floor to a seated person's eye
is 4'. That distance becomes the target for the direct beam of the projector. Again keep in mind that front
projection should be avoided except in the most extreme cases. If it is employed at all it must be used with
an extremely bright projector (2,500 lumens or greater for any space smaller than 25'x40').

Cameras

There usually is a "main" or "local people" camera positioned on top center of the display, so that it can "see"
the participants and anything necessary at the sides of the room, using pan and tilt features. If individual
presentations may be made from the side or "front of audience" area of the room, an additional camera
should be located at the back of the room, also mounted to allow a view of the presenters when necessary.
Some cameras contain an active camera pointing system that also can be used effectively, given proper
care in the mounting of the camera assembly. The area immediately surrounding the camera assembly
needs to be acoustically "dead" to ensure that the voice tracking and pointing algorithms work correctly. This
is another reason to pay close attention to the acoustic environment and acoustic treatment of any space
intended for use with this type of camera system.
If local presentation is blended with VC for any events, we must consider the needs of the presenter who
will not be "facing" the local image or inbound image displays used by the main body of the local audience.
One or two monitors (and a camera) should be mounted at the back of the "audience-end" of the room, with
the horizontal centerline at approximately 5' from the floor for ease of presentation interaction between the
presenter and the group(s) at the farend(s). Remember that, with the exception of PC-based information
that is not in a standard composite narrowband video format, any information we wish to "show" or "view"
must be translated to video, most often with some sort of camera mechanism. Document cameras, 35mm
slide-to-video units, video scanners and scan conversion devices all are designed to take one format of
source material and convert it to a standard video signal that can be digitized, shipped to the far-end(s), and
converted back to composite video for display. Which devices are selected and how they are used depends
entirely on the needs and goals of the end-users of the system(s) and the format of their source materials.
Room Control Elements
To give all participants the easiest use of the room for any and all presentation or conference purposes, a
fully integrated room controller is recommended. It is important that one controller operate all devices in the
room so that only one user interface needs to be learned by those managing the facility. The common
controller also makes it much easier to expand and enhance room capabilities over time by adding or
upgrading equipment. A proper room controller can operate and coordinate the use of lighting, curtains,
displays, audio devices, VCRs and slide projectors, as well as all the conferencing equipment, including any
network-related control needed. In lieu of a complete control system, a limited functionality controller can be
located at the presentation interface panel to control the switching and routing of the computer graphics and
configure the overhead camera video paths.
Polycom, Inc. 580