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Basic audio-visual equipment for webcasting

For most webcasting events the video and audio source will come from a single video camera, with possibly a radio microphone capturing the audio of the speaker. More complex setups are possible with multiple cameras and microphones for speakers and audiences, however this will typically require vision and sound mixers and is beyond the scope of this appendix. It is however worth noting that some webcast encoders are capable of supporting multiple video and audio feeds and mixing them within the software for example Wirecast (Varasoft), Live Channel Pro (ChannelStorm), or a hardware based solution such as Sony AWS-G500 Anycast Station (live streaming in Real Media only).

It is recommended that a DV video camera (Figure 2) is used in preference to web cams as web cams are typically designed for capturing video at a short distance and the quality of the video is likely to be poor in comparison to a DV camera. It is suggested 3 chip (CCDs) DV camera's are used as they will produce better images and will be more capable of handling difficult lighting conditions than single CCD DV cameras. Additional functionality we would recommend is Firewire (aka IEEE 1394 and iLink) input/output, good optical zoom, manual exposure controls and external microphone input.

Figure 2 : Sony DV Camera on Tripod

Figure 3 : Sennheiser Radio Mic and Receiver

Audio can be captured via the camera's own built-in microphones, however this is likely to pick up ambient noise and it is strongly recommended that a radio microphone and receiver are used, for example the Sennheiser G2 100 series (Figure 3). Used in combination with an external microphone input of the camera it is possible to record to the cameras tape as well feed the audio via the Firewire output to the encoder. Figure 4 illustrates a radio microphone receiver mounted on the camera and the Firewire and external microphone connections.

Figure 4 : Connection Details

Figure 5 : Desktop tripod

A tripod with a floating video camera head is highly recommended (Figure 2), however for more mobile webcasting it is possible to get small desktop tripods, such as the one illustrated in Figure 5.

Connection to the encoder is best achieved via a Firewire connection, however for older video cameras S-Video or Composite video can be used, together with microphone or line level inputs. Newer cameras may support USB2 however suitable drivers on the encoder PC may be required for the encoder software to see the camera.

Although most any video camera can be used, cameras such as network or IP cameras that capture and broadcast video over a network connection are not suitable for webcasting in the context of this paper, and are typically aimed at the security industry.

Suggested audio-visual equipment

Whilst there are many suitable alternative equipment sets that will work in a fit for purpose webcasting model, we recommend equipment with a similar specification to the following for this study.

Video Camera Camcorder

(3 CCD) Panasonic NV-GS400B MiniDV Digital
(1 CCD) Sony DCRHC96 Mini DV camcorder

Radio Microphone kit Sennheiser G2 100 series Radio Microphone and Receiver
Cables Firewire cable (4 to 6 pin, or 4 to 4 pin depending on PC encoder interface)
Tripod Slik U8000
Velbon Video CX-686 or Video CX-586
Table tripod Hama

Contact: Kevin Quick

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