Ronald 42212TNI, Installation Manual

Page: 57 / 68

57
MAXIMUM TARGET DETECTION DISTANCE
In general, the maximum altitude that a UFODAP camera might see a target would not
depend on the absolute altitude, per se, but rather the size, brightness and contrast of
the target.
"Seeing" might be defined as the target just covering enough pixels, with enough
brightness so that the tracking settings of the OTDAU software detect it. Those settings
can be as sensitive as about 3 pixels and very low contrast.
Another way one might want to quantify the ability to see a target is to specify its
resolution vs distance. The following calculations reference the image resolution
document listed below.
•
Assume a 30' diameter target object.
•
Assume the nominal 1920x1080 pixel camera image, with no zoom to start for
initial target detection.
•
Using the 50232XANR camera (32x zoom), focal length of 4.9 to 156mm, Sony
Starvis sensor (IMX290LLR) which is 4.56mm/side.
•
Rearranging the equations to get camera distance = ((pixels / (3 pixels/30')) *
(focal length / chip size) = ((1920 / (3/30)) * (4.9/4.56) = 20,631 feet or 3.9mi.
Of course, after target detection, with incremental zoom while staying on target, the
focal length and thus the distance greatly increases, thus putting more pixels on target.
As long as it is bright enough, even the initial target point of light would be adequate for
measurement by the Tracking Spectrometer.
Theia Technologies, a maker of lenses for security cameras similar to those specified
for UFODAP has published several useful guides on this subject:
Image resolution simulator and lens calculator -- https://www.theiatech.com/calculator
White papers, including “How to calculate image resolution” from which the calculations
above are derived --
https://www.theiatech.com/white-papers