Art Talk: Light & Color #1 (Patreon)
Content
Happy Friday! and Welcome to Art Talk! a new series of exclusive posts where I write about any art related thing I want, in any order and for as long as I want
some will be like tutorials, some will just be random thoughts, and all will be part of a series like this OR tagged accordingly for easy archiving.
to kick things off I'd like to start with my second favorite subject after color: Light
because most art is done in dark ink (or some other medium) on a light background, shading tends to get more focus than lighting...
but the trick to realistic shading, is an understanding of light and how it works.
the two main kinds of lighting being Direct & Ambient light.
ambient light is scattered light that fills a space and bounces off every object within that space.
think of how things look on a cloudy day, everything outside is brightly lit, but nothing seems to cast much of a shadow
this is because direct light from the sun is scattered (or diffused) by dense water molecules in the clouds and sent out in random directions, creating Ambient light:
this kind of light can get into every nook and cranny, and because it's not going in any particular direction, the shadows it casts are fuzzy and undefined.
a similar thing happens when you put a white shade over a lamp, light particals are scrambled by the material of the shade (the particles bouncing off the molecules that make up the shade's mass) and are sent out randomly, filling the room and hitting every uncovered surface
direct light, on the other hand, is what happens when light is cast or directed in a specific direction, like the light of a flash light, a laser, or the sun:
Direct light creates harsh shadows and is also responsible for things like highlights & Rim-lighting:
it's important to note, that direct light and Ambient light are not exactly separate, these are just different terms to describe the different ways light moves through a space
the biggest thing to remember here is that direct light moves in a straight line, but will BECOME Ambient light as it bounces around any given space
the most reflective or well lit objects in that space may even become secondary light sources, giving off a soft ambient glow that effects the overall color of a scene or the shadows & objects within said scene
this is something that happens to direct light from the sun. on a bright day, the sun will cast harsh shadows, but those shadows will be sublty illuminated by light bouncing off surrounding objects (earths atmosphere included)
this is why some shadows have a blue or green hue to them, they are subtly lit by the glow of the sky ( which gets it's hue from sunlight diffused by air molecules ) or nearby foliage ( light bouncing off green leaves ):
this is why empty spaces... like the deep ocean or an empty field at night, tend to have less ambient light, there are simply fewer objects available in the surrounding area to create it. this results in much deeper & darker shadows.
a great example of this is phenomenon is the moon and it's phases, because there's nothing close enough to reflect sunlight and illuminate it's dark side, the shaded areas of the moon appear pitch black:
and not only this, because the moon is too small to have an atmosphere and has no air around it to diffuse light from the sun, the sky on the moon is always pitch black as well
as a result of this daytime shadows on the moon have no color:
in most earthly situations, though, there is always something around to create ambient light, and these surrounding objects can drastically change the overall appearance of a scene:
for example; most of the light & color in the photo above actually comes from the floor instead of the window (the "real" light source).
because the wood of the floor is sienna in color, the ambient light it casts is also that color
some artists (myself included) will sometimes exaggerate this kind of lighting situation, using ambient reflections from an implied floor or a nearby wall to light the majority of a scene, I've started calling this trick "inverse" shading, but it still follows all the same basic rules of traditional methods.
to do something like this, you have to have a good sense of where your light is coming from and where it will eventually end up.
keeping track of how light moves can become very complicated very fast, so in a follow up to this post, I'll probably go over how to streamline this process, and when sources of ambient light can be focused on (or fabricated) for the sake of interesting lighting situations or ignored & removed for the sake of simplicity
the most important takeaway here though, is that a direct light source is only one half of the equation, and an understanding of light in general requires an understanding of ambient light as well.