Lighting an Interior Daytime Scene - Photographic Rendering with V-Ray for SketchUp - page 64

Testing our shot views
Having walked through the basic process of adding and configuring a V-Ray rect-
angle light in a scene, our next job is to enable them all and take some test renders
from our interior POV shot cameras. To do this, we could go into the V-Ray light ed-
itor and place a check in the Enabled option for each of the lights, one at a time. Or,
to speed things up a little, we could just load the Daylight_Interior_04.skp file
from the Exercise_Files folder which has all of the lights already turned on.
To get a clear idea of what our V-Ray Rectangle lights are contributing to the scene
(in terms of illumination), we ideally need to take a number of renders from our interi-
or views. Initially, I think we can take them using only the direct light contribution from
the rectangle lights, but then it may also be worth taking a couple with the global il-
lumination systems enabled. This will give us an idea of just how much light energy
these substitute skylights are going to bounce around the interior environment.
As a final test, perhaps we can then take a render that adds the key or sunlight into
the mix as well, giving us an opportunity to evaluate the ratio of key to fill light in the
scene. This will show us whether or not any final tweaks will be required.
In order to save our test renders for comparison, we could set things up so that the
images are saved directly to the hard disk using controls found in the Output rollout
of the options editor. However, we will take this opportunity to look at a very cool op-
tion that can be enabled on the V-Ray frame buffer window itself.
With the POV - Main Gallery Scene view selected, let's click on the render button
on the V-Ray toolbar to render our direct light image. Once that is finished, we can
go ahead and save it to the hard disk by using the render history feature of V-Ray
Version 2.0. This is a very handy set of tools that lets us quickly save the image
shown inside the V-Ray frame buffer window to the hard disk and then, at a later
point in time, load it back into the frame buffer for comparison with a different render.
To show how this works, perform the following steps:
1. Click on the H button found among the icons along the bottom of the V-Ray
Frame Buffer window.