Join Adam Crespi for an in-depth discussion in this video Creating the daylight system and positioning the sun, part of Maya: Rendering Interiors.
When we're lighting our interiors, we have a choice about what kind of lighting we can do. We can use the daylight system, projecting a good strong sun and bounce light from the sky into the room. We can also light it through interior lights, and even put in a sun using a directional light. Lastly, we can do sky portals, allowing the indirect light to bounce in through the windows. What I'll do first is light this scene with a daylight system, getting strong direct sunbeams coming in. When we do this, we should look carefully at the geometry we have, because that'll dictate how those sun shadows happen.
To start out then, I'll go into my perspective view, and pull up my render settings. And under the indirect lighting tab here in the Mental Ray rendering sections, I'll click Create next to physical sun and sky. This creates for me an MIA physical sky, which is a wrap around sky shader, and it's actually in control of the sun as well. It made a sun direction object, and plugged those into the camera along with a simple exposure. Now that I've created the sun, I need to put it in the right place. I'll use my outliner. Choosing Window and Outliner and filter down choosing Show > Objects and Lights, and selecting that sun.
Typically what I'll do is press Ctrl+ A to go to the attribute editor. Go into the object display and make locator scale something giant like 500. This is the drawn size of the icon on the view, not the physical scale. I'll press W for move and pull it out where I can see it. Although really it doesn't matter where it is, it matters which way it's pointing. Here's what's going on. This looks like a directional light, but actually all the properties of the directional light are being suppressed by the Mental Ray shaders here. Where it says suppress all Maya shaders, it means that everything above the Mental Ray section is moot at this point.
What's happening is that the MIA physical sun has been plugged into light shader and photon emitter. And those nodes are directly controlled by that physical sky, which is why we see the physical sky tab at the top of the attribute editor for the sun direction. The first thing I'll do with the sun then is put it in the right place, or rather orient it correctly to take advantage of my geometry. I'll rotate it by pressing E. And first, I'll angle it in. The default sun starts out at 12:00 noon, June 21st in San Rafael, California, which is where Autodesk is headquartered.
It's fairly straight overhead, and so there's not a lot of play on the light coming through those windows. I like to have my sun angled long and low. For example, unless somebody says the sun is coming in at this exact angle, what I tend to think of is wrong low winter sun in Southern California. That means the sun is big and bronzy, and slinking across all the surfaces. I'll angle it down diagonally looking at a front or left view, and then also in a top view pressing 4 for wire frame and F to frame selection, and I'll angle it across.
I'll press and hold E, left-click and hold anywhere and choose World, and now I'll rotate this sun on the y-axis to stream into that space. My usual guideline is this. I want the sun to come into the space diagonally in two views. Diagonally across in the top view, and in a front or left view. Again, aiming diagonally down not at a 45 degree angle. This simple trick of just making sure it's rotated properly, will ensure that all of your adjacent surfaces on corners read in different lights, and that you get the maximum reach out of your shapes casting shadows in that sun.
My windows and my skylights then will leave tremendous patterns all over the space, especially this Mondrian like grid of windows here. I'll go into my camera and test it out. I'll pull up my IPR window, choose Options > Test Resolution, and stop it down to 50%. I'll hit IPR again and run a region by dragging over it. Here's what we're seeing. I haven't done anything with the exposure yet. I also haven't changed anything in the sky. It's just the default setting. And I haven't changed final gather. So it's still got the default bounce of light going on.
Even with all those things unchanged from their starting values, it still looks pretty good. What I'm after here is that those shapes, those window frames, give me a tremendous reach of light and shadow into the space. And I've got a good luster going on on the wood decking underneath the bridge. Good lighting and bounce light happening from the stairs right onto that tile wall, and way up in the back of the scene, I can even see where one of the skylights is letting the sunlight through and onto the wall. This is my gauge, did I get the sunlight right? I want those beams to reach in there as long and as low as possible.
And get the maximum impact out of them before I consider, how does the light bounce in the scene.
- Creating and applying materials with luster and shine
- Creating a mental ray Daylight system
- Casting light from interior fixtures
- Lighting with sky portals
- Creating an ambient occlusion rendering pass
- Fine-tuning Final Gather and lighting
- Compositing in Nuke and After Effects
- Adding depth of field, highlights, and glow