Lighting an Interior Daytime Scene - Photographic Rendering with V-Ray for SketchUp - page 59

Skylight is our fill light
Just as it is obvious that in most daylight scenarios the Sun will be the dominant and
therefore key light, it is also very clear that without the secondary or Fill light that
comes from the Sky, what we call "natural daylight" would probably not look so natural
at all.
Essentially the Sky acts as a giant diffuse reflector that is able to cast at least some
level of illumination even into areas of an environment that direct Sunlight could never
hope to reach. In this respect, the Sun & Sky system form a perfect lighting partner-
ship—one that we often fail to fully appreciate for both its technical complexity as well
as its aesthetic beauty.
Besides adding almost perfect illumination coverage for an environment, we also
need to take into account the fact that Skylight can and often does add quite a strong
color cast. Again this is not something that we generally appreciate or possibly even
notice due to the automatic color balancing that our eyes and brain typically perform.
However, once we start to examine a naturally lit environment by means of photo-
graphic reference, especially when making use of varying exposure levels on the
camera, we start to see that the color cast added by a skylight can often be quite sig-
nificant.
Of course, in order to create our final render we are not obliged to stick rigidly to the
physics of real-world light, but if we are serious about creating a genuinely photo-
graphic image, such realities certainly need to figure (at least to some degree) in our
final lighting solution. It is, after all, the attention that goes into the sometimes subtler
details that will often times create a feeling or sense of genuine quality in a finished
piece of art.
To create a Skylight effect for an interior render we can again use a number of ap-
proaches in V-Ray by means of the different light tools available. The first option that
we will explore here is an older technique that involves making extensive use of V-
Ray's Rectangle light type.