- #1
mnb96
- 715
- 5
Hi,
I would like to get rid of the following misunderstanding.
Suppose we are looking to an idealized flat diffuse emitter perpendicular to the line of sight (like a wall). If we always face this wall but slowly walk away from it, the radiant flux that we receive from a small patch of that surface is supposed to decrease according to the square distance. In fact, the solid angle spanned by this small patch will decrease according to 1/r2.
However the object will appear having the same brightness instead of progressively fading to black, and become invisible...why?
I would like to get rid of the following misunderstanding.
Suppose we are looking to an idealized flat diffuse emitter perpendicular to the line of sight (like a wall). If we always face this wall but slowly walk away from it, the radiant flux that we receive from a small patch of that surface is supposed to decrease according to the square distance. In fact, the solid angle spanned by this small patch will decrease according to 1/r2.
However the object will appear having the same brightness instead of progressively fading to black, and become invisible...why?