iGen iGen-LE, Руководство пользователя

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Adjustable Features
intensity infrared at close range causes the device to reduce internal gain and increase
exposure time. Use of the IR MAX settings is only recommended in a very dark outdoor
environment.
Turning IR off at start-up
The default setting of the IR is AUTO. When the iGen powers on, it re-sets to AUTO
regardless of the mode it was set to before the prior power-down.
In order for the IR to be off upon power-up, set the IR-Start function to OFF with the
following menu choices: SYSTEM / IR-START / OFF.
4. Gain
The triple action switch adjusts the internal or electronic gain. There are a total of 10
different gain settings. These settings are preprogrammed and cannot be changed. Push to
the right and the image becomes brighter. At the highest gain settings, you will notice a
“noisy” or “snowy” image. As is the case with any night vision device, in very low light
conditions users will sacrifice image quality for light amplification. In order to recognize an
object or target under the very darkest conditions, it is usually preferable to see a lower
quality image than to see no image at all.
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Adjustable Features
7. Exposure
The most effective way to increase the low light sensitivity of the iGen is to increase the
exposure time of the system. In its default setting, the iGen collects light from the lens at
a rate of 30 times per second for processing. If this exposure time is increased, more
photons of light energy are collected, resulting in greater night-vision sensitivity. At the
default setting, the “shutter” remains open for 1/30th of a second and then closes and
passes the collected light on for processing. If we allow the “shutter” to remain open for
a longer period of time, we collect more photons and thus can “see” better at lower light
levels. The abbreviation “fps” means “frames per second.”
In a lighted indoor environment, you may notice a pulsing or strobing effect at varying
exposure settings. In the U.S., or other countries with 60 hertz electrical systems, exposure
rates other than 30fps and 15fps will be unsynchronized with the lighting system. The
iGen is designed for outdoor use and for use in dark environments so this characteristic
does not affect the device’s performance; such a pulsing effect will only be evident when
testing or practicing with the iGen in a lighted environment.
In countries with 50 hertz electrical systems, indoor pulsing may be apparent at many rates.
While light-gathering capability improves with longer exposure times, at exposure settings
below 15fps, the image may appear unnatural. Longer exposure settings (lower fps
numbers) present fewer and fewer image “snapshots” which are presented to you just as