Project 4b: Office Room Lighting

Before lighting any type of shot, you must think about the mood of the scene and what you want to the audience to focus on specifically in the overall composition. How you light a shot will determine how the audience's eye will be guided around the composition to the focal point. You can create compositions by the angles or shapes of different light values from elements such as shadows or highlights. (READ "LIGHTING FOR CINEMATOGRAPHY" to get more information about this particular topic). Colors are also very significant in the mood or the overall feeling of the shot. Color can heavily influence how one feels mentally and/or physically. For example, when a person sees the color red, they become more alert, their blood pressure rises slightly, and can become more aggressive in the way they talk or feel. However, when a person sees the color blue, it has the opposite affect. People can feel calm, peaceful, or sad.

Lighting is an art form, but is also very technical in software programs, as well as a science in the real world. In the real world, you have to think about how light waves mix, reflect, or get absorbed. Software can't capture all realistic attributes that light does in the real world, but there's definitely a lot of control and ways to make a scene feel believable. Because it's an art form, it means that there is more than one way to light a scene. Like painting, there is more than one way to create a painting from start to finish. Artists have their own techniques and methods, which is the same for lighting.

Overall when you begin to light:

• Think about the composition and mood. Where is the focal point? How can shadows and highlights be used to add interest and direct the eye towards the focal point?
  
  
• What time of day is it?
  
  
  
  Photo by Dirk Rabe: www.360cities.net/image/day-and-night-germany?
• Where is the main source of light coming from?
  
  

Other things to keep in mind:

• Where is there bounce light?
  
  
  
  "https://support.solidangle.com/display/AFCUG/SSS+Layers"
• How soft or hard should the light and shadows be?
  
  
• How will two colors of light mix? It's slightly different from mixing paint.
  
  "
  "http://sciencelearn.org.nz/Contexts/Light-and-Sight/Science-Ideas-and-Concepts/Colours-of-light"
• There is more than one way to light a scene.
• Consider why you're creating each light and its purpose in the composition. Things quickly get costly when trying to render. If you have a shot that's 200 frames long and it takes 3 minutes to render one frame, it would take 10 hours to finish rendering that one shot.
  
  

Render Layers

By default, Maya 2017 has hidden the render layers we will use for this assignment. In the bottom of the Channel Box, you'll see a Display and an Anim layer. In order to restore the Render tab to this location, go to Windows, Settings/Preferences, Preferences. Click Rendering on the side bar, and change "Preferred Render Setup system" to "Legacy Render Layers". You'll have to restart Maya after this change, but once you re-open you'll see a new Render tab in the Channel Box. We will need this later.

Light Linking

Light linking is the process of individually selecting which objects will be affected by which lights. We will use the Relationship Editor (Windows, Relationship Editors, Light Linking, Object Centric) extensively in this assignment to define relationships between lights and specific objects. To create connections between lights and objects (say, to connect a spotlight (spotlight1) to only one mesh (pcube1) in your scene as opposed to all of your objects), simply open the editor, click the object you want the light to affect, then the light. Lights that the object is connected to will be highlighted blue.

ATTENTION

Light linking can sometimes be a buggy process in maya. Make sure to give meainingful names to your lights

When you create a light, make sure you click on the light and move it around a tiny bit before putting in the lights values (scale, rotation, etc).

Open the provided office scene.ma file.

Think about where the focal point is and where the main source of light is coming from. There isn't a particular mood for this scene for the sake of demonstrating how all the lights work.

The main source of light will be from the lamp, not the window. It's later in the day and overcast, so the lamp will have a stronger source of light. The window will add in a soft fill light and will be less intense than the light from the lamp. Allowing the light from the lamp to be the key light will also create a nice diagonal shape, to guide the audience eyes from the lamp to the papers on the desk (the focal point).

Notice how aspects of three-point lighting is still being kept in mind; We're keeping in mind the keylight and how we're going to fill in shadows that are dark in value.

We also want to create a group of main lights that will give an overall sense of the scene, then add extra lights to make the composition more clear.

Once you're finished, you should end up with a scene that looks like this:


1. Create a spotlight and name it "lamp_key_light". Scale it up so that you can see it more easily.
   
   Position the lamp_key_light so that it is casting a light onto the objects on the desk and the desk itself. Simulate the light as if it is being cast by the lamp, you will probably have to play with the position of the light to make it look somewhat realistic.
   
   Give the lamp light an intensity value of 3.
   
   To make the edges of the actual light being casted softer, we are going to change the penumbra angle of the light to about 20.
   
   Go into the shadows tab and make sure "ray trace shadows" is checked and change the light radius to 5 and shadow ray value to 50 in order to get soft, but detailed shadows to be casted.
   
   Move the shadow color value slightly to the right to give it a very dark gray color to lighten the shadows being casted by the light.
   
   
   VERY IMPORTANT!

   Lighting is not a linear process. You may find later on that you'd like to change the way a light is linked to other objects, or its intensity, etc. That's normal and to be expected. Make sure to be constantly rendering as you work to see how your lights are looking.

2. Create an area light and name it window_fill_light and scale the light up to roughly the size of the window. Area lights are 2D rectangular light sources that are useful for a window light or ceiling lights. They simulate realistic light and softer shadows, and are higher quality compared to other lights. The downside to area lights is that they can become costly to render when shadows are turned on.
   
   Scale the light to be about the same size as the window and position it so that it is looking through the window at a downwards angle.
   
   Change the decay rate of the light to "quadratic". This will give the light a more realistic feel as light begins to fall off as it travels.
   
   Change the intensity value of the light to 1500 and the color to a soft blue/baby blue. Note: you might have to play with the intensity value depending on how far the light is from the objects and how large the area light is.
   
   Turn on ray trace shadows and change the shadow rays value to 50.
   
   Uncheck "emit specular" to remove any specular lighting because this will be added in later using another light.
   
   Lastly go to the "windows" tab at the top and drop down to "relationship editor" and then "light linking".
   
   Go to the relationship editor and switch to "object centric light linking".
   
   Make sure you unlink the "polaroid" and "papers_on_desk" group from the window light. To do this, click the "polaroid" and then click "window_light_fill". This will make it so that these objects don't receive any light. We will be lighting these objects separately with other lights.
3. Create a volume light and name it room_fill_volume. Volume lights emit light within a given visual boundary. In this case, the light will be contained with a box. Change the light shape to "box" under the "volume light attributes" tab.
   
   Scale the volume light up so that it looks something like this:
   
   
   
   Change the color to these settings: H: 32.622, S: 0.275, V: 1 (we want to use a yellow light to match the light being emitted from the lamp).
   
   Keep "illuminates by default" checked, but unlink the light from the papers on the table, the polaroid, and also the chair.
   
   Turn shadows on and set the light radius value to 10 and the shadow rays value to 50.
4. Create an ambient light and name it room_fill_ambient.
   
   Make the color of the ambient light the same as the color used in the "room_fill_volume" light.
   
   Change the intensity of the ambient light to 0.1.
   
   Ambient lights are nice because regardless of where they are placed in the scene, they will provide an even amount of light to all objects in the scene. This is a useful trick to use when you want fill in any really dark shadows or areas in your scene without having to individually light the spot. If used in the wrong way however, they can completely flatten a scene, and erase all depth. They should be used sparingly.
   
   
5. Create an area light, name it desk_fill_front, and scale it up to 28.85.
   
   Position the light so that it is pointing at the desk at an angle.
   
   
   Uncheck "illuminates by default".
   
   Change the decay rate to "quadratic".
   
   Change the intensity value to 500.
   
   Change the color to match your ambient light.
   
   Disable shadows.
   
   Only link this light to the desk and chair.
6. Create an area light, name it desk_fill_right_side, and scale it up to 28.85.
   
   Position the light so that it is pointing at the right side of the desk.
   
   
   Uncheck "illuminates by default".
   
   Change the decay rate to "quadratic".
   
   Change the intensity value to 250.
   
   Change the color to match the previous light.
   
   Disable shadows.
   
   Only link this light to the desk, chair and picture frame.
7. Create an area light, name it desk_fill_left_side, and scale it up to 28.85.
   
   Position the light so that it is pointing at the left side of the desk.
   
   
   Uncheck "illuminates by default".
   
   Change the decay rate to "quadratic".
   
   Change the intensity value to 150.
   
   Change the color to match the previous light.
   
   Disable shadows.
   
   Only link this light to the desk and chair.
   
   Uncheck "illuminates by default".
8. The lamp needs to have a bounce light that is filling it from the light reflecting off the table, we are going to use another source of light to fake the bounce light coming from the table.
   
   Create an area light, name it lamp_fill_light, and scale it similar to the size of the light seen in the image.
   
   
   
   The color should be the same as the other area lights we made for the desk.
   
   Turn off "illuminates by default" and only link the light to the lamp
   
   Turn off shadows.
   
   Change the Intensity value to 50 and the decay rate to "quadratic".
9. Create a volume light, name it lamp_inside_shade_light, and scale it similar to the size in the image.
   
   Place the volume light inside of the lamp head where the bulb is.
   
   
   
   Change the intensity of the light to 2.
   
   Change the color to the same color as the lamp_fill_light.
   
   Disable shadows.
   
   Uncheck "illuminates by default".
   
   Only link this light to the lamp.
10. The outside view needs a light, and because it's supposed to be a rainy dreary day, we are going to give it a tinge of blue by using a blue ambient light.
    
    Create an ambient light, name it outside_ambient_light, and change the intensity of the light to .750.
    
    Change the color to a cornflower blue or blue grayish color.
    
    Uncheck "illuminates by default" and have this light only linked to the outside view plane.
11. Earlier we disabled the specular attribute on our key light because we wanted to use a different light to be creating the specular on our objects.
    
    Create a spotlight, name it spec_light, and have it point into the room outside the window. Spotlights are the most standard type of light within Maya. They shine a beam of light evenly within a narrow range of directions that are defined by a cone. They are fairly cheap to render, and are very versatile.
    
    
    
    Turn off "illuminates by default" and link it only to the window and the lamp.
    
    Turn off emit diffuse but leave the specular on.
    
    Change the color of the light to the same color as the ambient light. This is because in this scene, the natural light outside is what is making the specular on the objects in the room.
    
    Change the intensity value of the light to .500.
    
    Set the penumbra angle to 20.
    
    Disable the shadows.
12. Now we want to add a rim light to the chair just to add some more realism to the scene.
    
    Create a spot light, name it chair_rim_light, and have it point at the chair as seen in the image. You have to play with it a little bit in order to get the camera to capture the correct angle of the rim light on the chair.
    
    
    
    Change the intensity of the light to 2.
    
    Change the color of the light to the same color as the lamp_fill_light.
    
    Set the penumbra angle to 20.
    
    Turn off shadows.
    
    Uncheck "illuminates by default" and link it only to the chair.
13. Create a spot light, name it lamp_fog_light, and uncheck "illuminates by default". Our scene is lit, we just need to add some fog to the lamp to make it look more visually appealing.
    
    Change the color of the light to the same color as the lamp fill light.
    
    Change the cone angle of the light to 50.
    
    
14. Group your lights. In your outliner, select all of your lights and press "Ctrl + G". Name the group "lights". This is an important part of lighting, especially in production.

Setting up an Occlusion Layer

Occlusion is another type of shadow that occurs in the real world, but cannot be generated when reading out a scene with lights in Maya. Instead, a shader with occlusion attributes is applied to all objects in a scene and rendered out. All the objects are white when rendered out with soft occlusion shadows on them. It doesn't take too long to set up.

Save your project before starting.

Since we're applying an occlusion shader to the entire scene in a new layer, select all mesh assets and all mesh parts of the set. When creating an occlusion layer, you never want anims or other materials in the layer, or else they will have occlusion shadows as well. So be careful and only select mesh. Then in the render layer box, click "Create new layer and assign selected objects" (), and all the mesh you selected will be placed in a new layer.

Name that layer, "occlusion_layer".

Make sure you have mental ray loaded as your renderer before continuing. (Windows, Settings/Preferences, Plug-in Manager, scroll down and check the box next to "Mayatomr.mll" to load it.)

Right-click on the layer and click on attributes.

Click on Presets, and then click on Occlusion in the list of layer options.

Rename the "surfaceShader#" to "occlusion_shader". If you look in the hypershade, you'll notice a shader node called occlusion_shader. If you didn't change the name, it will be surfaceshader#.

The Out Color attribute is where you can control the occlusion shader attributes. Click on the black arrow on the right side of out color.

Sample is the quality of the shadows. Higher the number, the less grainy the shadows will be and the longer it will take to render. Lower the number, less grainy the shadows will be. It's good to start somewhere like 250 and work your way up. If you play around with the value, you'll notice the quality change and render time changes.

There are two values to occlusion. By default it's white as bright (for the non-shadows parts of the objects) and black for the dark (the color of the occlusion shadow). Sometimes it's best not having pure black shadows, because it makes the image look muddy in colors when black mixes with other colors. Keep bright at white and dark at black.

Spread is the amount of occlusion spread you want on the objects. The best value for this depends on your set size and the distance between the camera and the objects with occlusion shader. Play around and see what value looks best. 1 is fine.

The Max Distance is how far rays will travel to find objects. The farther rays travel, the wider and shadow will be. If you decrease the distance of the rays, they create tighter shadows that appear when other geometry is very close to the surface. 10 is a good value to use.

Making White Hole Shaders

If there's an object that you don't want to have an occlusion shader, then you need to make a white_hole_shader. This is just a shader that renders out pure white, so that it doesn't look like it has any occlusion shadow on it.

At the moment, the occlusion layer has an occlusion shader override on all the objects in the scene. If you try to apply a new material it will not be able to apply, because the layer only wants an occlusion shader. To remove, right click on the layer and under "overrides", click on remove material override.

Right-click on the lamp shade and lamp bulb geo and assign a new material.

Make the material a "surface shader" and drag the out color value bar all the way to the right. This will turn it white. Or you can change the color by clicking on the color box and setting it to white.

Render

Go to your render settings().

Make sure your render settings look like this:

Make sure you are looking through your "render_cam" in your Viewport. (Select your render_cam, click "Panels" along the bar above your viewport, and select "Look Through Selected."

Select the occlusion layer and change the mode in the drop down menu from Normal to Multiply.

Open your render window() and make sure that all "render all layers" is checked.

• Go to render at the top of your render view window.
• Check "render all layers".
• This allows all render layers to be composited without having to go into photoshop or after effects to composite.

Render and save your scene.

For part B, you'll be establishing two moods for the same office scene. This where you're free to set up lights any way you want, as long as it invokes some kind of mood in the viewer. You will use the following moods: joy and sadness.

You can either find your own reference (Find 3 reference images for a mood), or use the paintovers and renders for reference. During production, or in industry, it's common for lighters to use color scripts or concept art to help get an idea how to light a particular scene.

Render out an image of your two mood scenes and save them to turn in with the reference you choose.

Paintover: Joy

Example Paintover: Sadness