Questions on Lights 1. Describe default lighting in a 3D scene?
It does not represent real world lighting, but it is simple and fast 2. What are the 4 elements of computer graphics lighting? 1. Intensity of the light 2. Color RGB values 3. Angle of incidence specifies 4. Light location 3. What is a point light? Give examples. Known as Omni Light, Shines light in all directions, good for acting like a candle, the sun is an Omni Light 4. Draw an example of how a point light would work in a scene? Can be used for the light of a candle or the sun in a scene
5. What is a spotlight? Throws light in a certain direction from a single point in space 6. Draw an example of how a spotlight would work in a scene? Label all of the parts. Good for the headlights of a car in a dark scene in a forest or the lights on a stage of a dancer in front of a large crowd
7. What is ambient light? Light that simulates the overall light in the world around you 8. Draw an example of ambient light in a scene? Good for filling the scene with overall light
9. What is infinite light? Simulates the Sun by producing light rays that are parallel to each other, all objects in the scene receive the same amount of light 10. Draw an example of how infinite light would work in a scene?
11. List two things color light is used for? 1. Special effects 2. Used to emphasis time 12. What do the following colors represent in a scene? Yellow cast Pinkish tint Bright White Softer white light Hard and sharp white light In Moods what do these colors represent? Red, orange, and yellow Green Blue In Temperature, what do these Red Blue Late afternoon scene Represent mornings Represent noon Morning Light Mid-afternoon ---------------------------------------------Anger or passion Peacefulness Sadness or depression colors represent? -------------------------Hot Warmth Cold Coolness
13. What happens when you add more light to a scene? The longer the render times and the more RAM you will need 14. How many lights make up a classic layout in a 3D scene? ___3 types of light____ 15. What is a key light?
The primary light source in the scene usually placed off to the side of the main feature in the scene. It is the strongest, brightest light. Typically it is the only light in the scene set to cast shadows. Local lights and spotlights are often used as key lights.
16. Fill light? The fill light is usually 25% 50% the strength of the key light and is used to add enough light to soften the light provided by the key and to reduce or eliminate unwanted shadows. Needs to the placed opposite of the key light
17. Backlight? Backlight creates a defining edge to help visually separate the subject from the background. It adds depth to the scene by separating the objects from the background, giving them more of a defined shape.
18. Draw a typical light set up in a 3D scene.
19. In lighting moods what is a high key light? High key lighting places the key light in front of and above the items in the scene to create interior, daylight scene.
20. In lighting moods what is a low key light? Low key lighting is a key light placed lower in the scene than in the High Key setup. It is used in night scenes to simulate the light of the moon and stars
21. In lighting moods what is a frontal light?
It places the key in front of the scene, but it also places the key high above the scene to produce an effect similar to an overhead light would produce.
22. In lighting moods what is a side light? Side lighting places the key light at eye level and in front of the scene to produce light that simulates sunlight.
23. What is attenuation? Attenuation simulates the diminishing (fading) of a lights intensity over a distance
24. Decay? Decay measures the amount of fade or lessening of intensity.
25. Falloff? Falloff describes how the light energy is dispersed.
26. Squared falloff? Squared falloff most closely simulates light in the real world.
27. What role do shadows play in a scene? Shadows have an important role in lighting; shadows add depth and realism to a scene. The angle of your light source determines the length and size of the shadows.
