Physics/Science of Light (PART 6)

Physics/Science of Light

(How you could implement it + create dramatic compelling art scenes)

The Fresnel Effect

Fresnel was a physicist who came up with series of equations that solved various problems associated with the science/physics of light. If you were to have a conversation with physicists they'll probably know more about the Fresnel equations than the Fresnel effect.

The idea behind the Fresnel effect is when you get any type of reflection you're not going to get a perfect reproduction of that image. During this process, the light is lost inconsistently. I'm sure there are multiple explanations which exist that explain this more elaborately, but I'll keep it concise and definitive.

Let's look at it this way: many atoms are evenly spread out in the centre of the reflected surface of the sphere, but along the edges of the sphere the atoms become more tightly knit and compressed. The compression reaches a critical density and this density in essence affects the properties along the edges of the sphere. This alteration in the properties along the edges causes a distorted sense of reflection.

This is the Fresnel effect. As the angle of incidence along with the angel of reflection increases- so does the strength of the reflection.

Different materials have different levels of interactions that determine the strength of the Fresnel effect. Water is one of the common surfaces that substantially gets affected by this phenomenon.

If we were to view the pond at an angle then that transparency starts to diminish and we start getting a strong reflection of the sky and the surroundings reflected unto the water. That is also the Fresnel effect. To reiterate, if you stand at the edge of a lake or clear pond you'll see from the distance that the surface takes on a mirror reflection of the atmosphere (except it is an inverted version). With this type of reflectivity, you are no longer able to see through the surface. As that angle gets more extreme so does the reflection. Whereas if we're looking straight down at the water there would be minimal reflection and the water would still be transparent enough for you to see through it.

If you're drawing a reflection on a ball-the center of the ball will be least reflective and the edges will be most reflective.