FLIR PatrolIR B, User Manual, Page: 19 / 36

427-0026-01-10, version 110 Oct 2010 15
3 – Getting Started
The camera automatically adjusts to changing scene conditions.
However, the camera does contain four preset conditions that might
provide better imagery in certain conditions.
The thermal imager inside the camera does not sense light like
conventional cameras; it senses heat or temperature differences.
As you experiment with the system during daylight and nighttime
operation, you will notice differences in the picture quality; this is
normal. The camera senses small “differences” in apparent radiation
from the objects in view, and, in
white hot mode, displays them as
either white (or lighter shades of gray) for warmer objects, and black
(or darker shades of gray) for colder objects.
This is why you will see areas such as exhaust stacks or engines that
appear white (or black, or red depending on the video image mode
selected), while the rest of a vehicle may appear dark (or cool).
Scenes with familiar objects will be easy to interpret with some
experience. The camera automatically optimizes the image to
provide you with the best contrast in most conditions.
Thermal (radiant) energy emitted by objects that were warmed by
the sun during the day can be reflected, in much the same way
sunlight can be reflected. Do not assume that the objects you are
looking for will be hot and therefore show up as white. Look for
variations or anomalies in scenes that you think would normally be
the same temperature.
As you experiment with your PatrolIR B, you will see your world in a
different light. Consider every object you view in terms of how it will
look “thermally” as opposed to how it looks in the visible spectrum.
For example, after sunset, objects warmed by the sun will radiate for
several hours and will appear warmest right after sunset. Early in
the morning, many of these objects will appear cooler than their
surroundings, so be sure to look for subtle differences in the scene,
as opposed to just hot (white) targets.
Environmental conditions, including time of day, humidity, and
precipitation, will affect the image quality. For example, the radiation
of an object will be affected by even a thin layer of dew. The diurnal
cycle that causes objects to heat up in the sun (this is known as
solar loading) and cool off at night will also have an impact on the
image. The range of temperatures of objects that appear in the