Hmm, I think I got it. My 1st attempt anyway. I just chose specs for a really good camera circa 2015.
Sensor size physical height: 40 mm - (Imax is 52 mm)
Compare digital camera sensor sizes: 1″-Type, 4/3, APS-C, full frame 35mm
Sensor's picture height: 4912 pixels (common HQ DSLRs)
Camera tech data for Sony NEX-VG20E
Distance to object = 8200 meters (statute)
Object height in pixels: 6
Object width in pixels: 11
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Height of real object:
Lens focal length 18 mm = 22 meters
Lens focal length 300 mm = 1.35 meters
Width of real object:
Lens focal length 18 mm = meters 40.5 meters
Lens focal length 300 mm = 2.45 meters
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One thing to consider is the footage shown is at a much lower resolution according to the source.., which makes the object smaller.
We need to find out the video resolution we are seeing, get a size of the object in pixels, compared the output to the Raytheon AN/ASQ- 228 video resolution.., and estimate the upsize.
I.e. I would guess the footage is 480 and the camera recorded at 1080, which adds at least 2 to height, and 3 to width.
CAMERA - SIZE OF OBJECT
16mm lens: 33.9 meters X 58.43 meters
300mm lens: 1.78 meters X 3.12 meters