Adjustments
(continued)
4. Gain
The 3-way 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, it is preferable to see a lower resolution image than to see no image at all.
5. Color
Both the color of the image and the color of the menu text can be changed. Image color
choices are white, red, green, and blue. Text color choices are black & white, green, red,
and amber. The color green is typically used in night vision applications because the rod
cells in the human eye are most sensitive to the green wavelengths of light, 550nm. You
are better able to distinguish details when displayed in the color green. The color red can
be useful when you want to maintain your unassisted vision in the dark when you look
away from the viewer.
6. Brightness
The display brightness has 4 settings. The default setting is 3. The darkest is 1; the
brightest is 4. As the display is a major consumer of battery power, darker brightness
settings will prolong battery life.
Access the brightness control by first choosing “display” from the menu and then
choosing the brightness option.
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” at lower light levels.
The abbreviation “fps” means “frames per second.”
In a lighted indoor environment, you may notice a pulsing or strobe effect at varying
exposure settings. In the U.S., or other countries with 60hertz 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 will be apparent at all frame rates.
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Infrared Emitter
The basic principle employed by iGen is light amplification. In very dark conditions, where you
cannot see, and your eye cannot detect the small amount of light that is available, the iGen
detects and amplifies very small amounts of available light. But in the absence of any
available light, use the infrared emitter.
To understand how much light is available in different environments, review the following
table. Light intensity is measured in lux. One lux is roughly the amount of light created by a
candle at a distance of one meter.
The number of lux existing in different environments is:
Condition
Number of Lux
iGen Function.
Sunny Day
100,000+
Too bright. Keep lens cap on.
Overcast Day
100 to 10,000
Too bright. Keep lens cap on.
Indoor Lighting
80 to 300
Keep lens cap on.
Street lighting at night
1 to 10
No IR(infrared emitter) needed.
Full Moon
0.1
No IR needed.
Quarter Moon
0.01
IR might be needed.
Clear night with no moon
0.001
IR necessary at distance.
Dark Cloudy Night
0.0001
IR absolutely necessary.
Night Vision technology works by amplifying the small amounts of light energy available in
most dark environments. If you are in an environment where there is NO LIGHT available to
amplify, then the mathematical formula:
zero times
any number = zero (0 x N = 0)
describes what you can see without assistance from an infrared emitter – nothing.
For this reason, the iGen is equipped with an active infrared emitter. iGen emits an invisible
beam of near-infrared light. The beam of light exiting the emitter is not visible to human or
animal eyes but is detected by the iGen and reproduced on the display. In most
environments, you do not need the infrared emitter, but in complete darkness, turn the IR on
to the AUTO or MAX settings. The default setting of the IR at start-up is the AUTO mode.
Also notice that while the light emitting from the IR is invisible, the diode does glow a bright
red inside the emitter and can be detected from a distance. If you wish to remain completely
concealed, then do not use the infrared emitter.
CAUTION:
Do not point INFRARED directly into eye at close range
Keep out of reach of children
The infrared emitter emits a BRIGHT, although invisible, beam of light. It is not a laser, but
like any bright light, you do not want to point it directly into your eye.
The infrared light emission is produced by a light emitting diode, similar to those used in
modern flashlights.
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