FLIR mariner, Руководство оператора

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3 – Getting Started
12 11/06 427-0010-00-10, version 120
When using the ThermoVision
®
Mariner as a navigation aid, keep an eye
out for objects in the water that may be appear only slightly warmer or
colder than the surrounding water. You will notice that in some cases, as in
Figure 3-7, you can see thermal reflections of warmer objects on the
water. Thermal (radiant) energy emitted by these objects that were warmed
by the sun during the day can be reflected by the water, 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.
In some cases, the composition of the object you are looking at can make
it look warmer or colder, and therefore be more or less obvious to your eye.
In Figure 3-8, you will see an object off the starboard bow that appears as
a small white line. This happens to be a log that was floating in the
Willamette River in November at about 7PM. Although this log was likely
the same temperature as the surrounding water, its composition makes it
appear white like a hot object. The important thing to note is that there is
clearly something in the water and you should carefully navigate to avoid a
collision. You can also see that there is a marker just off the port bow, at
about 100 yards.
Figure 3-7: Mariner showing thermal reflections on the water