Vicon VC2430B, Руководство по установке и эксплуатации

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ELC/ALC Select Switch (EE/ELC is ON; ALC/AI is OFF)
This switch is used to select EE (electronic exposure)/ELC (electronic light control)
mode or AI (autoiris lens)/ALC (automatic light control) mode. Pole 1 is set to ON
for EE/ELC and OFF for AI/ALC.
In the EE/ELC mode, a continuously variable electronic shutter is employed to
automatically control the exposure time of the CCD image sensor according to the
incoming light level. With this mode selected, a fixed or manual iris lens can be used
instead of an autoiris lens. In the AI/ALC mode, the CCD shutter speed is fixed to
1/60 (1/50) sec, and the incoming light level is controlled by the autoiris lens.
To use a video-drive type or the DC-drive type of autoiris lens, set this switch to the
ALC position.
Cautions :
1. Under bright lighting conditions such as outdoors, use an autoiris lens because the
EE/ELC control range is not wide enough under these conditions.
2. Under certain unique lighting conditions, the following phenomena may appear:
ƒ
Strong smear and/or blooming on highlight objects such as spotlights or
windows.
ƒ
Noticeable flicker in the picture and/or color rendition variations. To avoid this,
use an autoiris lens.
3. When operating in EE/ELC mode with manual iris lens, the depth of field of the
image may be less than that obtained by using an AI/ALC lens. Depth of field varies
inversely with the iris opening. Thus, using this camera in EE/ELC mode with the
manual iris lens fully opened may result in less depth of field and the distant objects in
a picture may be seen out of focus.
4. Fixed iris or manual iris lenses may be used with the linear shutter (EE/ELC mode)
where the scene brightness varies over a limited range.
5. Do not use the EE/ELC mode when an autoiris lens is installed.
CONNECTORS AND CONTROLS