Cinema 4D Handbook: Chapter 6, Part I

27Sep11

All through September I am going through the Cinema 4D, r10 Handbook in hopes of gaining a new skill and better understanding of 3D modeling. I plan to (from here on out) cover two chapters a week (longer chapters will be broken into multiple posts). Stay tuned for new chapters.

Chapter 6: Lighting, Part I

Coming from a film background, I’ve been finding this chapter right up my alley. The basics of lighting on a set and lighting a 3D environment are extremely similar. The book says that without lighting, 3D models are bland, and the true is same in the real world. Chapter 6 focused more on the techniques of lighting than the technical how-to; I will model my blog like that as well. However, the book also recommends using the Help menu for reference on “every little button and slider available to you in C4D’s basic lighting system, including types of lights, types of shadows, etc.”
To access the Help menu:
Help> Help. Choose Content, Reference> Objects> Scene Objects> Light Object

As part of the lighting process, Cinema 4D separates materials from lights, because both influence the way a model looks. “The computer separates, both for conceptual and practical reasons, objects that emit light from objects that receive light.” Because of this, finalizing the way a model is lit is a process of adjust lights, adjusting materials, adjusting lights, and so on.

Tutorial 6.1: Three Point Lighting

Just like in traditional film sets, 3-point lighting for animation is made of Key Lights, Fill Lights, and Back Lights. You can alter the way a scene looks by changing the intensity ratio between the Key and Fill lights to create High Key/ Low Key lighting. “Three-point lighting is best used for lighting objects and less so for lighting environments.”

The Relationship Between Camera Angle and Lighting
When you start to move the camera angle or position, the lighting may change. A spot light coming from behind an object will look different as you move around that object.

The Key Light
The Key Light is the principal light for a scene. It casts shadows and acts as a starting point for your lighting setup.
To Add a Spot Light (as the Key):
A spot light is a directional light that creates a cone of light on an object.
1) Create a new Spot Light. Objects> Scene> Spot light
2) Rename the light. The book recommends naming lights by the direction, type, and color.
3) Use the Attributes Manager to adjust the color and position of the light.
4) Render the scene. Shift+R
5) Re-adjust the light settings to what you want it to be.

The Fill Light
The Fill Light is used to reduce shadows and dark areas. The Fill Light does just that, it fills the darkened areas that the Key Light creates.
To Add an Omni Light (as the Fill):
An omni light is a light that shines in all directions.
1) Create a new Omni Light. Objects> Scene> Light
2) Rename the light. The book recommends naming lights by the direction, type, and color.
3) Use the Attributes Manager to adjust the color and position of the light.
4) Render the scene. Shift+R
5) Re-adjust the light settings to what you want.




Low Key vs. High Key Lighting
You can create specific moods in your scene by using High Key or Low Key lighting. Determining whether your scene is high or low-key means looking at the ratio of the intensity. If you’ve set the intensity of your Key to 100% and you Fill to 10%, then you have high contrast, or “High Key.”  Likewise, if your Key is at 100%, but your Fill is much closer, say 80%, then it is considered “Low Key,” because there isn’t as much contrast

You can control whether your scene is High or Low Key by changing the intensity of the lights, or by adding multiple lights. If you have two fill lights (at 40% and at 10%) then they’re combined intensity is 50%. That means the ration of Key to Fill is 2:1.

Backlighting
The last type of light in a 3-point setup is the Backlight. The backlight serves as a separation light. Adding a backlight to a scene can make an object pop out from the background.
To Add a Backlight:
1) Create and Omni Light. Objects> Scene> Light
2) Rename the light.
3) Add an Array Object. Objects> Modeling> Array
4) Link the light to the Array. *NOTE: By linking an omni light to and array, you will have the ability to create soft even light in a circle.
5) Render the scene.
6) Change the attributes of the Backlight and of the Array object to create the look you want.

Refining the Scene
You can further refine scenes by using Include/ Exclude. In the Attributes Manager of a light there is a “Scene” tab. Inside that tab you can drag and drop elements to be included or excluded by that light.

You can also create a light with Negative Intensity. It breaks the laws of physics, but in 3D, you can create a light that can actually suck light off of an object. By changing the intensity of a light to a negative number you can target certain areas of an object that are too bright and suck some of the light out of it.





Tutorial 6.2: Area Lighting

“Area lighting imitates the bounced and diffuse light that is achievable through global illuminations.” You start with a main light, the add secondary lights that look like they’ve been bounced off of an object. In this tutorial there are four walls, a statue, and lights. The walls have been colored, and the main light comes from over the statue. The bounce lights will be created to fill out the scene.

The Main Light
An Area Light is a flood light that mimic lights that have area or volume. If you can see a light in a scene, and it emits light, then that is an area light.
To Create an Area Light:
1) Add an Area Light. Objects> Scene> Area Light
2) Rename the light.
3) Change the light’s position to match that of the Light Object (the viewable fixture).
4) Change the light’s attributes to match what you want.
5) Render the scene.
6) Adjust the light’s attributes and exclude any objects that need to be.

Bounce Lights
The Area Light creates a harsh shadow on the model, to lessen the effects of the shadow, we add secondary Bounce Lights. Bounce Lights mimic the light that is being bounced off the walls in the scene.
To Make an Area Light for the Walls:
1) Create an Area Light. Objects> Scene> Area Light
2) Rename the light and reposition it so it’s over the left wall.
3) Use the Attributes Manager to change the color to match the wall’s color.
4) Adjust the light’s properties in the Attributes Manager. Be sure to increase the falloff rate. *NOTE: Falloff is the amount that the light weakens over time.
5) Add the “Left Wall” object to the Exclude list.
6) Render the scene then make changes as needed.
7) Repeat these steps for the back, right, and front walls. *NOTE: The front wall is unseen, and its color should be white.

Adjusting the Shadows
As it stands right now, the scene has very harsh shadows. By changing the shadow type and sample rate you can create more realistic models. It also takes more processing power and will increase the total render time of the scene.
To Adjust the Shadows:
1) Select all of the lights in the Objects Manager.
2) In the Attributes Manager, change “Shadow Type” to Area.
3) Go into the Shadow tab and change the Samples to 70.






The final render of the scene should look more realistic. Area Lighting and Three Point Lighting are two basic ways to light a scene. They mimic real world lighting situations and were a piece of cake for me to pick up on (as they should be for anyone used to working with lights on a film set). The next few tutorials may give me some issue (more based in the 3D world), but I look forward to doing them tonight. Their review should be put up tomorrow.

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One Response to “Cinema 4D Handbook: Chapter 6, Part I”


  1. 1 Cinema 4D Handbook: Chapter 6, Part II « Widen Media Blog

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