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Day Night Colour Infrared Light Emitting Diode (Night Vision)
Security Cameras Colour CCTV Day
Night Cameras with inbuilt Infrared
Light Emitting Diodes "See-in-the-Dark" and produce images when
visible illumination is zero.
At average levels of illumination these Cameras
produce Colour images, depending
on their sensitivity (Lux) at low illumination levels and in total
darkness the image is Monochrome.
These Cameras generally have a relatively high
sensitivity image sensor and
Fixed
Iris Lens therefore under high illumination levels images will
be overexposed for the reasons outlined
here, an exception is
MINI-COL-IR which has a special Wide Dynamic Range allowing it
to cope with higher illumination levels than ordinary Cameras.
Ordinary CCTV Colour Cameras are relatively
insensitive to Infrared because they have an IR CUT Filter between
the Lens and Image Sensor, this filter excludes Infrared radiation
with a wavelength greater than ~ 700 nm that would otherwise
adversely affect White Balance, Colour Rendition and Image
Sharpness.
Day / Night Colour CCTV Cameras are sensitive to
Infrared because they either do not have an IR CUT Filter or utilise
a special NOTCH IR CUT Filter that excludes the wavelengths most
harmful to colour quality (720 ~ 830 nm) from reaching the Image
Sensor.
A Colour Camera that does not have an IR CUT
Filter usually has poor colour
rendition characterised by a
Pink-Red
'tint' when the illumination is InfraRed rich,
use of a 'Notch' Filter helps however White Balance,
Colour Rendition and Image Sharpness are compromised
for Infrared sensitivity. (Image Sharpness can be restored by using
a specially designed Lens that corrects the focus shift between
Visible and Infrared)
The IDEAL Day / Night Infrared Sensitive
Colour CCTV Camera would utilise an Automatic
Iris Lens to cope with high illumination levels and the Lens
would also have a large aperture (low 'F' number) to maximise light
transmission when illumination levels are low * it would also
utilise a Traditional IR CUT Filter when illumination levels are
adequate for Colour and then REMOVE the IR CUT Filter when
levels are low
Dome-DayNite,
Maxi-DayNite,
Dome-D/NiteEx,
Maxi-D/NiteEx &
CCS-IRdnWD have these features and are
recommended for OPTIMUM results - the ULTIMATE
SOLUTION is
AutoCam-dn or
DomePTZ-dn these also have Automatic-Focus
to ensure crisp images under all conditions.
Infrared rich light
sources include Daylight and most Filament type lamps including
common Spot lamps, Tungsten lamps, Halogen lamps, etc.
The majority of Light emitted from 'Cold' type
sources such as Fluorescent, Mercury Vapour, Sodium Vapour, etc., is
visible, these sources contain little Infrared energy.
SUMMARY: "See-in-the-Dark"
Infrared capability is a trade-off that
affects Colour Quality particularly in "Infrared Rich" environments.
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Ideal
for use with 720 H-Pixel
Air