Business and Computing Deanery Multimedia Week 20 Lighting

Multimedia 2 Last week Animation Cameras Video Streaming Compression Production

Multimedia 3 This week Realtime and photorealistic Rendering Lighting concepts Types of lighting Shadows

Multimedia 4 Realtime v. photorealistic Compare lighting OpenGL - max 8 Photorealistic – 10 per character Convergence of realtime and photorealistic Realtime is now used to plan real movies Used extensively in games

Multimedia 5 Internal or 3 rd party Traditional The CG production pipeline Story Art Set design Layout Animation Shading Modelling Rendering Lighting Simulation Effects Film Commercial Editorial

Multimedia 6 Rendering The act of translating the information in the files that make up the shot into a single frame of film Rendering "fills in" geometry with color, shadow, lighting effects, etc. Pixar have created Renderman 10 years ago it took 6 hours to render one frame How many today? Use render farms

Multimedia 7 Concepts Light has warmth (yellowish) or coolness (bluish) Intensity Angle if incidence Radiosity Light reflecting from an object Attenuation Light becomes weaker with distance 3ds max v7

Multimedia 8 Lighting basics Three main sources of lighting in classic photography Key Fill Backlight Concepts apply to 3D programs, plus Ambient light

Multimedia 9 Getting it right 3ds max v7

Multimedia 10 Key light Outdoors The sun Indoors Major window Main electric light Flash on a camera Spot light on a stage

Multimedia 11 Fill and key lights Fills in the dark shadows cast by the key light Outdoors may be created artificially Indoors from secondary lights Distant window Light fitting Softens shadows 3ds max v7

Multimedia 12 Backlight Situated behind the subject Separates the foreground from the background Can make the scene more three- dimensional

Multimedia 13 Lighting strategies 3ds max v7

Multimedia 14 Planning lighting Default lighting Use this until you are happy with the scene, then add lights Use as few as possible Start with the key light Maybe a spot Add fill Use omni or several spots Finally add accent lighting 3ds max v7

Multimedia 15 Ambient light Not a light source Light from other sources bouncing of walls, the ceiling and other objects in the scene 3ds max v7

Multimedia 16 Types of lighting Standard Spotlights Omnidirectional light Directional light Advanced Photometric lights

Multimedia 17 Spotlights Casts a focused beam of light like a flashlight, a follow spot in a theatre, or a car headlight 3ds max v7

Multimedia 18 Omnidirectional light Known as omni light Like a bare light bulb Casts rays in all directions from a single source 3ds max v7

Multimedia 19 Directional light Also known as Distant lights Cast parallel light rays Primarily used to simulate sunlight

Multimedia 20 Target lights Concept like cameras Target Easier to aim Simply position the target object at the centre of interest Free 3ds max v7

Multimedia 21 Lighting direction Single light from side Single light straight on Both sides Reduced full fill 3ds max v7

Multimedia 22 Activity Open up your model of a room, save with a new file namse Add one or more spotlights to provide lighting and render the scene Experiment with moving them around and rendering the effect Add an omni light behind the scene Alter the values to achieve a balanced rendering

Multimedia 23 Standard light settings Intensity Angle of incidence Attenuation Reflected light and ambient light Colour

Multimedia 24 Attenuation Natural reduction of light intensity 3ds max v7

Multimedia 25 Brightness and colour Intensity sets the brightness of the scene Range from 0 to 255 (white) Colour – use the RGB sliders 3ds max v7

Multimedia 26 Activity With your scene experiment with your light settings Vary the light settings for: Intensity Angle of incidence Attenuation Reflected light and ambient light Colour

Multimedia 27 Use of shadows Default lighting Spot plus low level back lighting Spot 3ds max v7

Multimedia 28 Shadows Photometric and standard lights both have the same options for generating shadows Two types Shadow mapped Ray-traced

Multimedia 29 Shadow mapped Grayscaled texture map based on the lighting and mesh Soft-edged More natural May be blocky May be inaccurate May be incorrectly positioned Do not take transparency into account Do not take on the colour cast of the object May use a lot of RAM 3ds max v7

Multimedia 30 Ray traced shadows Ray tracing techniques Have a hard edge Software can be used to soften Very accurate and precise Does not use a lot of RAM 3ds max v7

Multimedia 31 Hotspot and falloff Hotspot Angle of the inner portion of the beam Falloff Angle of the outer beam Differences in angles make the effect softer 3ds max v7

Multimedia 32 Include and exclude Some software allows you to set up lights that affect only certain objects Use a pick list to select objects

Multimedia 33 Colour and mood Cool colours – blues and violets Still and calm Warm colours – yellows, red and orange Fiery and energetic Intense and active Be careful, keep it subtle

Multimedia 34 Activity Create a flat surface with a sphere and a cone sitting on top Add a spot light Add a fill light Alter the hotspot/fallout Alter the type of shadow

Multimedia 35 Photometric lights Photometric lights enable you to more accurately define lights as they would be in the real world using ray tracing Distribution, intensity, colour temperature can be set 3ds max v7

Multimedia 36 Global Illumination with Radiosity Standard lights are simpler than natural lighting Using photometric lights with a radiosity solution with your lights provides a better model of the real world Radiosity is rendering technology that realistically simulates the way in which light interacts in an environment

Multimedia 37 Preset photometric lights Generic 60W Bulb Generic 75W Bulb Generic 100W Bulb Generic Halogen Spotlight Generic Recessed 75W Lamp (web) Generic Recessed 75W Wallwash (web) Generic Recessed 250W Wallwash (web) Generic 4ft Pendant Fluorescent (web) Generic 4ft Cove Fluorescent (web) Generic Street 400W Lamp (web) Generic Stadium 100W Lamp (web)

Multimedia 38 Photometric lights Target Point Similar to a standard omni light, emits light from a geometric point Spotlight Focused beam Web distribution Distribution of light Many lighting manufacturers provide web files that model their products 3ds max v7

Multimedia 39 Sunlight and Daylight A system that follows the geographically correct angle and movement of the sun over the earth at a given location You can choose Location Date and time Compass orientation. 3ds max v7

Multimedia 40 Daylight Daylight combines sunlight and skylight The sunlight component can be either IES Sun light Illuminating Engineering Society Values set automatically based on geographic location, time, and date Or a standard light (a target direct light). The sky component can be either an IES Sky light Or a Skylight.

Multimedia 41 Self assessment You have been asked to model a lecture theatre for Hope Compare and contrast the lighting required for A guest lecture without note taking A lecture with note taking and discussion sessions

Multimedia 42 For Next Week Submit your Portfolio 2.2 Work on the 3ds max tutorials Directed reading chapter 6 and 10 Giambruno M, (2002) 3D Graphics & Animation, 2nd Edition

Multimedia 43 References Giambruno M, (2002) 3D Graphics & Animation, 2nd Edition, New Riders, ISBN: Kerlow I. V., (2003) The Art of 3-D Computer Animation and Effects, 3rd Edition, John Wiley & Sons Inc; ISBN: Murdock K.L., (2005) 3DS Max 7 Bible, John Wiley & Sons Inc, ISBN: Screen shots taken from 3ds max 7 User Reference