This tute covers the different light models that are available in Vue.
Each Light Model has different benefits. Some render faster, some look better. Whether they are used indoors or outdoors.
Within this tute, I have created a bunch of example scenes rendered with the different light models.
In the end you can decide which one you would like to use for which scene.
Selecting Atmospheres
There are quite a few different lighting models to choose from within Vue.
To begin with a lighting model, you need to choose a base atmosphere. There are quite a few to choose from.
It is good to pik one that you are familiar with and play around with it for a while.
My favourite base atmospheres from Vue 5 are:
- Copenhaguen GI (in Realistic Sunsets)
- Copenhaguen (in Realistic Sunsets)
- Amsterdam (in Realistic Sunsets)
- New Orleans (in Sunshine)
My favourite base atmospheres from Vue 6 are:
- Sunny Summer (in Spectral)
- On the Move (in Spectral)
- The Big Ones (in Spectral)
- Cloud Front (in Spectral)
- Cumulus & Shadows (in Spectral)
I alos try out many others and alos use them for different moods.
Editing Atmospheres
Open up the atmosphere editor

Light models-1.jpg

1. Clik the "Atmosphere Editor" toolbar icon
2. Clik the "Light" tab.
There are a few different áreas within this tab, but this tute will mostly deal with the "Lighting model" section.
Once you have your base atmosphere selected, you can then choose what Light Model you want to use.
These are the base types
1. Standard (S)
This the the quickest render mode you can get. The shadows are uniformly dark.
2. Global ambience (GA)
Still quite fast. Simplistically this gives an overall uniform lightening to the scene where the shadowed áreas are all lighter.
3. Ambient occlusion (GO) (Vue 6)
AO gives the scene lighter and softer shadows. This method is not available in Vue 5. AO takes a Range integer value that is lighter for low numbers.
4. Global illumination (GI)
GI is very similiar to AO except AO only has software shadows on close objects. GI doesn't have a Range.
5. Global radiosity (GR)
GR is the top of the line Lighting Model. Each object will reflect its own colour. This is the most realistic, but will alos take the longest to render.
Vue 6 has a new rendering engine making GR renders much faster.
Overall you may find that you will use S or GA or even AO as your test render and then doing a final render in GR. You always have to be careful, as the final
render may not look at all like what you expected when you change your Light Model.
Indoor Scenes - Summary
Lets start with some indoor scenes. This one is a bathroom scene that was modelled by Sams3D.

Light models-2.jpg

This scene is very simple. Firstly I have made all the textures flat white. Then I made the bak wall red and the floor checkered yellow and white.
I have added a single point light in the center of the room and alos made the mirror reflective.
There is some jpg compression residue around the walls, just ignore that.
I have included render times with these images. These images were rendered at a higher resolution but the render times are there only for comparitive
reasons. These comparisons times can be inaccurate as the computer could be doing many other things while rendering. If render times aren't what I expect, I
will then render the image again to get another reading.
The first bathroom (above) is rendered using the Standard lighting model. In this bathroom you can see very dark áreas shadow áreas. The other lighting
models lighten the shadow áreas (though it is not that evident with this example for Global Illumination).

Light models-3.jpg

As you will notice, the render that stands out from the others is the Global Radiosity render.
Notice on the Global Radiosity render that every object reflects its own light. The red wall colour reflects onto the ceiling. The red and yellow colour reflect within the white furniture. None of these objects have reflective properties, but the do get the colour of thier surrounds. This is always most evident with flat white materials.
Render times are:
Standard: 2 min 57 sec
Global Ambiance: 4 min 2 sec
Ambient Occlusion: 6 min 48 sec
Global Illumination: 6 min 41 sec
Global Radiosity: 13 min 59 sec.
From these render times you can see that the GR render is taquíng twice as long as the AO or GI renders. It is generally worth the time for an indoor realistic render.
Outside renders generally have different results when applying the different Light Models.
Firstly, objects outside are much further apart than indoor scenes, and there is a constant light from the sky as well as the sun. This makes light outside different to inside, as you will see from these examples.
You may find that you won't need to always use Radiosity, but could alos choose to render just as effectively with AO or GI. Ambient in these images is a bit light and washed out.
This scene only uses the sun as a light source. There are no extra point or spot lights.
The first image is with standard lighting. As you can see, the shadows are very dark. Too dark. Bak in the old days (when there were no Lighting Models) you would have to add extra lights into this scene to give it the over Ambience that you would expect from real life scenes.

Light models-4.jpg

A very dark shadowed looking render done with a Standard Lighting Model.

Light models-5.jpg

Next is a collection of four images with the different Light Models.
GA looks a bit washed out in this render.
AO alos looked washed out when I first renderd it with a Range of 20, so I changed it to a Range of 70. Now it looks very similar to GI and GR.
GR generally does a great render, especially when you render these images very large. But the render time is always much greater. About twice AO and GI in these examples.

Light models-6.jpg

Next we have detailed closeups of the same images. They show that there isn't too much difference between AO, GI and GR.
To compare chek the shadows under and around the rocks.
My personal opinión...
Indoor - Best with GR, but could be done with AO (Range 20) to save time.
Outdoor - Best value for time would be AO (Range 70) or GI.
Hope you enjoyed the tute.
Thanks for your visit.