Project 4b: Room Lighting
Part 1: Match the Lighting
For the first part of this assignment you are to match the provided image's lighting to the best of your ability.
- Download the Maya file and the target image.
- Constantly save iterations while you work! When you begin to add multiple lights in the scene, Maya will have a lot to calculate and could possibly crash. It's a good habit to always save your work in order to save you time if something happens with Maya.
- Use a variety of light types and experiment. Be aware that depth map shadows and some lighting effects with Maya Software will not work with raytracing.
- For a basic explanation of each light type check out the light creation section of the Maya help documentation.
- Organize!Create a group in your outliner (Ctrl+g) and call it "lights". All of your light should go in here! You can also subdivide this group for further organization. Also be sure to name your lights in a logical manner, including information on what objects they are hitting and their purpose. For example: lamp_shade_fill, lamp_light_on_wall
- Link your Lights.By default new lights hit every object in the scene. Most of the time this isn't necessarily what you want.
- Go to light's attribute and un-check "Illuminates by Default". .
- Go to Window → Relationship Editor → Light Linking → Light-centric (You may want to tear off this panel while working on this assignment)
- On the left is a list of all the lights in your scene, on the right is a list of every light-receiving object in the scene.
- Select the light you want on the left and then the objects and/or groups of objects you want that light to affect on the right.
- Make sure to use raytrace shadows and to render in mental ray.
While working you will want to use preview render settings. To do so, go to Windows → Rendering Editors → Render Settings, then go to Presets → Load Preset → Preview. Be sure to change the preset back to Production for your final render.
- DO NOT use Photoshop to tweak the lights in your scene. Do all your work in Maya.
- DO NOT change geometry, shaders or camera settings. This project is only about "painting" your scene with light.
- Render your scene.Go to Windows → Rendering Editors → Render Settings. Make sure to use the production quality preset. In the common tab change the image format to PNG. Scroll down to the Image Size section and make sure the Width is 1024 and the Height is 768. Next, hit the render button, making sure the render from render_cam. Save the image by right clicking on the rendered image and go to File → save Image. Name it (lastname)_(firstname)_part1_beauty.png
Your "beauty" render is your high quality render straight out of Maya with no additional render passes. You will learn more about additional types of render passes later in the course.
- Render an occlusion pass. (OPTIONAL)
- Below the channel box is the layer window. Click on the Render tab. Select all the physical objects in your scene besides the view_outside object (do not select any lights or texture placement nodes). Go to Layers → Create Layer From Selected. Rename your layer to occlusion pass by double clicking the layer name. .
- Right click the layer and select Attributes. Make sure the occlusion tab is selected. Go to Presets → Occlusion.
- Change samples to 250, Spread to 1, and Max Distance to 3.
- Make sure the render layer is selected and render from camera_1.
- Bring both renders into separate layers in Photoshop. Make sure the occlusion layer is above the rendered scene. Use the Multiply Blend Node and save your image.
- Suggested Lights for Main Key Light
- Area Light
In Maya, area lights are two-dimensional rectangular light sources. Use area lights to simulate the rectangular reflections of windows on surfaces.
Compared to other light sources, area lights can take longer to render, but they can produce higher quality light and shadows. Area lights are particularly good for high-quality still images, but less advantageous for longer animations where rendering speed is crucial.
Area lights are physically based-there is no need for a decay option. The angles formed with the area light and the point that is shaded determine the illumination. As the point moves further away from the area light, the angle decreases and illumination decreases, much like decay.
Can achieve a very pretty look without much tweaking, but tends to add significantly to render time.
- Directional Light
Use a directional light to simulate a very distant point light source (for example, the sun as viewed from the surface of the Earth).
A directional light shines evenly in one direction only. Its light rays are parallel to each other, as if emitted perpendicular from an infinitely large plane. It's simple, straightforward, and low cost for rendering. It only points one direction, unlike the area light.
- Area Light
- Suggested Lights for Lamp Light
- Point Light
A point light shines evenly in all directions from an infinitely small point in space. Use a point light to simulate an incandescent light bulb or a star.
- Create (2) Spot Lights
A spot light shines a beam of light evenly within a narrow range of directions that are defined by a cone. The rotation of the spot light determines where the beam is aimed. The width of the cone determines how narrow or broad the beam of light is. You can adjust the softness of the light to create or eliminate the harsh circle of projected light. You can also project image maps from spot lights.
Use a spot light to create a beam of light that gradually becomes wider (for example, a flashlight or car headlight)
- Point Light
- Suggested Lights for Fill/Bounce Light
You can use spotlights, area lights(area has prettier lighting, but higher render cost).
- Ambient Light
Be careful with ambient lights and making things look too flat.
A Maya ambient light shines in two ways-some of the light shines evenly in all directions from the location of the light (similar to a point light), and some of the light shines evenly in all directions from all directions (as if emitted from the inner surface of an infinitely large sphere).
Use an ambient light to simulate a combination of direct light (for example, a lamp) and indirect light (lamp light reflected off the walls of a room).
- Ambient Light
- Suggested Lights for Contact Shadows
- Shadow Light
This will help make sure things don't look like they're floating.
With the production workspace installed, there is a button (
) on the Production shelf that automatically converts a selected light to a shadow light. Once converted you can still move the light around and modify its attributes. However, you will need to setup your light linking before the conversion. The shadow light setup also assumes you are using Mentalray and raytracing, and will not work with Maya Software.
If the automatic method does not work to your liking, you can also set up a shadow light manually. Below are the steps you will need to take to do so:
- Make a spotlight and name it (object casting shadow)_shadow_light. example: lamp_shadow_light
- Go to the light attributes and uncheck Illuminates by Default.
- Under the Shadows section make sure Use Ray Trace Shadows is checked.
- Link it to the thing that is casting the shadow and the thing that the shadows are being casted on -for example, the floor.
- Leave the intensity at 1. You will adjust this up or down as needed as this is how you will control the darkness/intensity of the shadow.
- Position the light where you want it.
- Duplicate the light. (Ctrl+d)
- Name the copy of your light (object casting shadow)_negative_light. example: lamp_negative_light
- Turn off shadows.
- Link it to the same objects as the shadow light. Duplicate does not copy your light links.
- Make the intensity of your negative light the exact opposite of your shadow light (-1 if the shadow light is 1, etc)
- Render and adjust as needed. Remember this light will need to have the exact same position, cone angle and penumbra setting as your shadow light. This means that if you change anything on the shadow light you will also have to change it on the negative light.
- Shadow Light
- More notes on Shadows!
Note that the shadows cast from objects in this room may not actually be cast by the key light(s). You do not have to use your key light to cast shadows, but this light (or these lights) do indicate the direction the shadows are coming from. So if you create extra lights to cast shadows, be consistent on the direction of shadows that would be casted from the main key light.
- Light Pools
Notice the pools of deeper shadow and bright light. This adds depth to the space and helps direct the eye. Avoid lighting everything too evenly.
- Fog Lights
There are a few ways to create light rays through your windows. Here is one: Light Rays 101
You can also achieve a similar effect by adding a light fog to a spotlight.
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For the second part of the assignment, you will pick a specific mood from the following list: Sad, happy, or fearful. Be sure to select two reference images that inspire you. The staff and students will guess which mood you've selected so prepare by showing friends and family and getting their response. Indicate your chosen mood by commenting in the Catalyst turn-in area for Project 4b.
- Gather Reference. Gather at least two pieces of visual reference that supports the theme (day or night) and mood you have chosen. The references you choose can be paintings, photographs, film, ect. Use the reference to adjust your lights to accentuate the mood you are working with. This could involve shifting the colors (say to green if you are going for fear, for example), the contrast or the angle of the lights and sharpness or length of shadows.
- The ultimate goal is to convey a particular mood with your lighting. Pay close attention the distribution of light and color throughout your scene. Bad lighting is typically very flat, while good lighting contains gradations. It is generally more visually interesting to juxtapose at least two colors.
- Motivate your lights as much as possible. This means that the viewer should be able to understand where each light is coming from, whether it is a window, light fixture, or even just bounce light. This is a fairly loose guideline, but one you should think about. You should also use contact shadows where needed. An object on the ground typically casts a shadow below it. If you forget these shadows, your overall lighting will suffer for it.
- Lighting is an art, not a science. Use Reference. However, the purpose of reference is not to provide you with something to copy, but to show you what good lighting looks like
- Make sure we can see your scene. Pools of dark and dim light can be effective when deployed in the right places, but if the overall brightness level is so dark that it is difficult to see what is going on, then that is no good.
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Experiment! You may have noticed the fog effect coming through the window in the scene you matched, below is a link to instruct for how to achieve the affect. You can also project images though lights (lower left picture) and many other things.
Play with effects and don't hesitate to try things, but always remember that if you use an effect it still has to support your mood.
- The same restriction from before apply. Don't touch up the lights using programs like photoshop, and keep geometry/shaders/camera as they are, and make sure the render using mental ray.
- Render your scene. Use mentalray and the same setting specified in Part 1. Save your file as (lastname)_(firstname)_part2_(mood)_beauty.png
- Render an occlusion pass. (This is optional)
Tips To Help You Out: Breakdown of Various Light Sources
Take a look at this breakdown of various light sources, fills and shadows in the room. Think about the approach you will need to take for lighting the different parts of the scene. Note that there are also some tips on what light types you may want to use to get you headed in the right direction.
Part 2: Mood Lighting