What is the value of perspective in number ?

[VishwasG]

Hi!
I wanna know, the value of perspective in exact number.
Like how much is the angular convergence between two points


A. Camera ----------------------------------------------------------- Building B.


In the above how much would building converge, and what would be the size, when viewed at point A.

Thanks
V.

[HallsofIvy]

Your question is much too vague. Your object has to have some size in order to subtend an angle. If building B has height h, and the distance from camera A is x, then the angle between the base of B and top of B, as seen from camera A, is arctan(h/x). Is that what you are asking?

[VishwasG]

Thanks,
So, you mean it would change as per the distance between eye(camera) and the view(building) ?

But what is the answer, if i replace the building with horizon ? How would i know the distance of horizon from my eye ?

Nevermind.. got it here :
http://en.wikipedia.org/wiki/Horizon

Thanks.