Physics/Science of Light (PART 10)

Physics/Science of Light

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

ATMOSPHERIC EFFECTS

There are three ways that atmosphere reacts to light.

1. Emit Light

There's light emitting atmosphere- such as a nebula, plasmas, fire, (which either they emit their own light or react to something else or other energy that's hitting them and creating light.)

2.Scatter Light

Then there's light scattering atmospheric effects, in this case you can see the blue of the sky coming through the clouds. It's filtering down through the clouds which allows a lot of light to pass through the haze and scatter back towards our eyes. Of course as the light passes through the cloud it must also get past the rain which causes excessive scattering. In most cases, the light travelling through the atmosphere gets redirected and bounced in several directions during the process.

(explain with the diagram next to it)

3. Block Light

Light blocking; this could be caused by either a dense atmosphere which causes regular scattering

OR

it can be caused by an atmosphere which absorbs either part of the spectrum or just blocks the light completely due to the density or size of the particles.

While examining it is evident that a fair amount of light is coming through these clouds along the edges as opposed to the clouds at the bottom which are getting very dark.

ATMOSPHERIC PERSPECTIVE

One of the main point you need to understand before you paint atmospheric perspective is to determine what is in the air. Whether its humidity, fog, along with the characteristic structures of oxygen and nitrogen in the atmosphere. One of things you'll notice in atmospheric perspective is that closer objects have an increased amount of contrast; they possess dramatic gradations of lights and darks. Whereas as objects get further away the amount of contrast is reduced because of the particle in-between (ie. air, water particles) the viewer and the distant object.

This happens because the light is coming down from the sky, bouncing off the earth there and either light being occluded/blocked by these particles or it being scattered by those particles.

With distance, as things get farther away, the volume between us and the particles in the atmosphere is going to increase. As a result, this will cause a dramatic loss in details of distant objects. In most cases we'll lose the shadows first in distant objects.

In most cases atmospheric perspective is very subtle.Usually most atmospheric effects like haze, smoke, fog, and humidity tend to be very gray. So the resulting colour that we'll see will be a combination of the light coming down (which gives it a warm tone to the scene) and the particles in the atmosphere.

Any atmosphere lowers contrast of distant objects, visually affecting shadows more than highlights.