Add Physical Sky illumination and background.
- [Narrator] The Arnold physical sky environment provides illumination and a back drop through an Arnold SkyDome light. The Ai physical sky is a simulation that's photometrically accurate. Let's go ahead and open up the Arnold Render view. Arnold, Render. And then create the physical sky back in the menus Arnold, Lights, Physical Sky. And we see something now in our Arnold Render view.
There's a sphere at the origin. That's an Ai SkyDome light. Select it and we can see it's an Ai SkyDome. Let's open its attributes with Control + A. And we saw the attributes for the SkyDome in a previous movie. The only thing we want to do in this case is increase the samples to five. And that will get a higher quality rendering. We can also make this sphere larger. Scroll down to the Viewport section and set the sky radius to 70,000.
We won't see anything in the background here but at least we don't have this distracting sphere over there Now let's go to the Ai physical sky parameters. We can get to that either from the Go To input node button in the Color attribute for the SkyDome light, or just by going directly to the node tab in the Attribute editor, for Ai physical sky. The first thing we want to look at is Elevation in Azimuth. Elevation is the height in degrees above the horizon line.
And Azimuth is the position in the sky left to right. We can drag the Elevation slider down and as we do, we see some light up here in the Arnold Render view. Set the Elevation to 23 degrees, press Enter, and then bring the Azimuth over as well. Drag that to the left and we can see, there's a tiny spot of light, and it's actually the sun. Let's set the Azimuth to a value of 60 degrees.
And there's that tiny sun, little spot of light there. Increase the Sun Size attribute to a value of two. And now the sun is large enough in the frame. At the top of the Physical Sky Attributes is Turbidity, that's the amount of haze in the atmosphere. We can drag that down and that'll cause the color of the sky to become more blue. Set Turbidity to a value of one. Having done that, we've reduced the overall brightness, so we can increase the Intensity here.
Set that to a value of four. And now we've got a pretty good exposure. But we can art direct this better by tinting the sky and the sun. Let's make the sunlight more orange. Click on the Sun Tint color sample. And in the color picker, set the Hue for the sun to 50, press tab, and set the Saturation to 0.5, and press Enter. Leave the Value at it's default of one. And now we've got some orange sunlight in the Render view.
Let's also tint the sky to make it more blue. Click on Sky Tint, the color sample, set the Hue to 214, press tab, Saturation 0.5, press tab, and Value of 0.7, and press Enter. Now I've got a much richer blue in the sky. And having done that we probably want to increase the Intensity once again. Let's bring that to a value of nine.
And now we've got a bright daylight shot with a blue sky. And that's how easy it is to set up the attributes for a physical sky environment map in an Arnold SkyDome light.
- Arnold rendering concepts
- Lighting with Maya and Arnold lights
- Controlling exposure
- Filtering light with Gobo
- Light attenuation with Decay
- Image-based lighting with Skydome
- Exterior daylight with Physical Sky
- Arnold Standard Surface material attributes
- Mapping material attributes
- Rendering refractions
- Mesh subdivision and displacement at render time
- Shading effects such as ambient occlusion and vertex color
- Camera effects such as fisheye and depth of field
- Animation image sequence rendering