Angle of view
From ScienceZero
d is the dimension of the sensor in the same slant as you want to know the angle of view (horizontally, vertically or diagonally but any slant is possible). f is the effective focal length of the lens.
- <math>\alpha = 2 \arctan \frac {d} {2 f}</math>
Arctan (Inverse Tangent) can be found as atan or tan-1 on some calculators.
