# Thread: Help with simple goniometrics

1. ## Help with simple goniometrics

Hi heres my problem -

tan(α/2) = (l/2)/d, hence
α = 2*atan(l/2d)

with this formula I can calculate the horizontal field-of-view of my camera.

I found it at this site - Determining the viewing angle of your camera

Only I havent a scientific calculator or the where with all to solve this!

I need to find a - the angle of view.
I know that l is the width - 2290mm
and I know that d is the distance - 5000mm

Any help from your forum members would be great! please save me any more days trawling endless websites trying to make sense of this!

Thanks
JayT

2. Is your problem that you don't know how to compute this, or that you don't have a scientific calculator.
You can enter this in google: 2*atan(2290/(2*5000)) and Windows has a built in calculator, which you can expand using the "Scientific" option.
The answer you'll get is in radians, which you can convert to degrees by multiplying it by $\frac{360}{2\pi}$

3. IN google I got the answer25.7966711

I will see how this suits thanks for the help

4. yea the answer you got is right