Campbell CCFC, Руководство по эксплуатации продукта

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FIGURE 14-43. Night Mode
IR LED power control
WARNING:
The IR LEDs emit a very bright light that is nearly invisible to the human eye. Do not look
directly at the front of the camera when the LEDs are on, as they can cause severe eye
damage.
The infrared (IR) LEDs on the camera are used to take pictures and video at night. To enable the
IR LEDs, select the Night Mode page.
When the IR LEDs are enabled, the camera automatically switches them on and off during photo
or video capture when the ambient light level drops too low. Generally, this happens shortly after
sunset outdoors. The IR LEDs remain on while the camera is awake. If the camera is configured to
use a low power mode, the IR LEDs will turn off when the camera goes to sleep.
The IR LEDs and the lens defroster are multiplexed together, so only one will operate at a time. In
a situation where both the IR LEDs and the defroster should be on, the IR LEDs take priority as
they also provide a significant amount of heat to the lens.
The IR LEDs emit light at 850 nm wavelength in a 20° cone from the centerline. This is a fairly
narrow beam angle, which concentrates the light on the center of the photo, allowing distant
objects up to 36m (120 ft) away to be illuminated.
Filter control
Outdoor photos contain a great deal of IR light from the sun. The photo sensor in the CCFC is
sensitive to this IR light and will pick it up causing the photo to look improperly colored. The lens
on the CCFC is equipped with a switchable IR filter to counteract this effect.
The setting for the IR filter allows it to be enabled all the time or disabled when the camera is in
night mode, giving the camera extra sensitivity in dark scenes without having to use the IR LEDs.
CCFC Field Camera 99