IES (Illuminating Engineering Society) These are files that are the physical attributes of any given light bulb. When applied to a light in 3ds max, the correct patterns and illuminance are displayed
Lens Effects These are the camera lens ‘balls’ as seen when sunlight is filmed. Preferably not used as CGI is about the ability to recreate reality not film.
Glare This is the streak effect produce by atmospherics. A camera lens and moisture in the human eye will give streetlights at night the starry look.
Glow This is the aura around a light source. If used as a shader, it is calculated at the point of render but will not affect other objects. If used with self illumination in an Arch & Design material, it will affect it’s surroundings.
Caustics These are the effects of light as it passes through an object with an Refraction Index greater than 1 (or Air) Most popular caustics are the patterns on the seabed created by the sun or the patterns thrown on a tablecloth by light passing through a glass of wine.
Ambient Occlusion This is a greyscale render that creates shadows where geometry meets. It is sometimes called a ‘dirt’ pass and is used in conjunction with a direct illumination pass and composited together. Developed by Industrial Light & Magic whilst making ‘Pearl Harbour’.
Volumetrics This is the art of filling a volume with density i.e. Lights & Fog. Volume light can be used where the atmosphere is full of dust, fog, rain etc. Volume Fog is just that! Can be used in conjunction with Atmopheric Apparatus.
Index of Refraction This is how light is viewed through an object that has a greater density than air. An example would be a glass of water. Glass has a refractive index of 1.52 and water is 1.33. If a pencil or straw is placed into it, it will appear bent due to the IOR.
Inverse Square Law This is a law of physics whereby radiation dissipates from the source at a rate dictated by a mathematical formula. For radiation see lighting, heat, gravity; in fact anything that radiates in three dimensions
Final Gather Final gathering is an optional, additional step to calculating global illumination. Using a photon map to calculate global illumination can cause rendering artefacts such as dark corners and low-frequency variations in the lighting. You can reduce or eliminate these artefacts by turning on final gathering, which increases the number of rays used to calculate global illumination. Final gathering can greatly increase rendering time. It is most useful for scenes with overall diffuse lighting, less useful for scenes with bright spots of indirect illumination such as focused caustics.
Global Illumination This enhances the realism in rendered images by simulating all light inter-reflection effects in a scene (except caustics). It generates such effects as "colour bleeding."
Remember... the early bird might get the worm, but the second mouse always gets the cheese!