Datum markings
We always used square painted markings on the aircraft ( Harrier 1 & 2 ), stores to be released such as bombs were usually painted in black & white quadrants.
We asked the test range/s what would be easiest to see / film with kine-theodolite tracking cameras, the reply was " don't bother, any aircraft always looks black against the sky ".
The datum points were useful for on-board cameras though.