3Ds MAX lighting; concepts and techniquesBY: RANDHIR PRASAD YADAV

Properties of Light Intensity/Luminosity Intensity and luminosity are similar concepts. The following two images

illustrate the difference.

Direction

Diffuseness

In general, diffuse light is any light that has been scattered after leavingthe light source, or any light source that has a varying area of luminosityor intensity. Scattering can be caused by atmospheric gases or by reflection, or bounce, off an uneven or rough surface.

Shadow

Shadows are not technically a quality of light. While some may teach that

lights cast shadows, in fact it is objects that cast shadows. A shadow isthe absence of light and therefore cannot generally be considered a lightquality.

Contrast

Contrast refers to the range of difference between the lightest parts of

the image and the darkest parts. An image in which the lightest parts aremuch lighter than the darkest parts is considered to have high contrast.

Size

Interior or Exterior

Time of Day

sun

skylight

Specularity and Glossiness

Reflectivity and Diffuse Color

Luminosity

The key lighting a scene is the primary source of light. It can be any lightsource from any angle. It is the light that provides primary illumination.Sunlight is an easy example.

The Fill Light

Fill light does two main things. Most obviously, it illuminates areas that are shad-owed from the key light. It also usually illuminates all the areas that are

lit by the key light, or at least some of them where the key light and filllight overlap on a surface. In other words, in a situation with a key lightand fill light, the shadows are illuminated by the fill light and theunshadowed areas are illuminated by the key light and the fill light wher-ever they overlap.

The Highlight

The highlight is also known as the top light, the back light, the tip light,

and the rim light, depending on where you learned your lighting. Its pri -mary purpose is to make an object stand out from its background, to helpdefine the shape, and to provide a nice, defined edge for those nastygreen-screen or blue-screen shots.

Three-Point Lighting

Three-point lighting is a simple, versatile, and powerful method of pro-viding an immediate “beauty” lighting scenario in which most elementsare likely to be visible and attractively lit. The key light provides primaryillumination, the fill light provides form and shadow fill, and the highlight provides dimension.Three-point lighting using spotlights is also extremely fast to renderwith shadow maps.No scene or lighting analysis is necessary, and the artist can importa generic three-point lighting rig from a prepared scene any time, scalethe rig, and start a render.

What Is Great about Three-Point Lighting

Ambient Light

Ambient light doesn’t exist in the real world, although it is meant toapproximate some lighting behavior we see every day. In the real world,light reflects from one surface to the next over and over, perhaps mil -lions of times, until all the light energy has been absorbed. This isknown as radiosity. Radiosity has the effect of giving an overall brighterappearance to any environment and occurs everywhere all the time.

IES Sky

“IES” refers to the Illuminating Engineering Society. Wherever you seethese letters, it means a bunch of physicists have gotten very pickyabout the light behavior, and while you may not even notice the differ-ence or it might not seem to work the way you’d like, don’t worry—atleast it’s physically accurate.

IES Sun

IES Sun is another photometrically accurate lighting instrument and isintended to be used with IES Sky for outdoor lighting environments.Once again, being the creative people we are, we certainly aren’t obligedto use the tools exactly as directed. I can throw an IES sunlight and anIES skylight together any time I want without using the Daylight Sys-tem and I will probably never be jailed for it.