Bryce 5 has several very powerful and controllable artificial light sources, or "light objects" as I like to call them. They:

• behave like objects-- you can size them (which changes the effect of some types of lights) and place them anywhere in your scene.
• Can be animated-- you can move them during an animation, just like objects and you can animate light controls to create effects, such as a light coming on or going off.
• Can have a material applied to them -- a light "gel" or a gradient to create interesting shadow/light effects

There are many controls in the Light Lab to manage artificial lights in Bryce 5. We'll look at them and how they apply to a radial light. The principles work with all artificial light sources in Bryce 5. This is a very detailed subject, but well worth understanding because Bryce 5 really shines (pun intended) when it comes to lighting!

NOTE: Ambient light continues to affect a scene that uses artificial light. The Sun and Moon light is still active unless turned OFF in the Sky Lab. Keeping them ON and positioning them to best advantage can increase your effectiveness and "mood" lighting projects. We show this at the end of this tutorial.

Note: We'll do a LOT by the numbers. I always indicate negative numbers in RED INK.

Put a Light Source in The Scene:

Open the model used in the previous section: Ambient Light.

In the Create palette, click on the radial light. It will appear in your scene.

Click on the light and set the following in the Attributes box:

Position:

X = 0, Y = 48, Z = 90

Name: Light

You can leave the rest at their default values.

The size of a radial light object is a convenience for moving it around in a scene. It has no effect on the amount of light. That is controlled in the Light Lab. So we can use the default size.

Our light is now placed in the vertical (up and down) center of the room, and is under the ceiling fixture dome light we created. This is a convenience for this tutorial. Position the light this way allows us to use a single light to illuminate the scene as if the ceiling fixture was doing it.

Our ambient light from the Sun is still in the same place, Azimuth 90 and Altitude 45. We'll keep it there for now, and at the end, change these settings to see their effects.

The Light Lab:

We'll do a lot of work in the Light Lab, just as we have been doing in the Sky Lab.

Make sure your scene is set to Camera view, and then click on the Light and then the E to open the Light Lab. In the Light Lab make sure Cast Shadows is turned ON.

There are a LOT of controls here to play with. But first, click on the down pointing triangle under the NANO preview and choose "Render in Scene" and "Fast Preview". This way we can instantly see the effects of our light settings.

Now here's a little bit about what all those controls in the Lab mean.

NOTE: The Bryce 5 manual covers them in greater detail, so be sure and look there for more information!

Intensity: This is the amount of light generated. Think of it like the power rating on a light bulb.

Edge Softness: Used with spot and parallel lights, it softens the edges of the light. Does not apply to radial lights.

Cast Shadows: Makes objects cast shadows when hit by artificial light. Sky Shadows must be turned ON in the Sky Lab for this feature to have any effect, and the setting in the Sky Lab (we have been using 50) determines the intensity of the shadows. Multiple lights can have shadows on or off independently.

Shadow Ambience: Allows you to apply a color wash to shadows. Using this will INCREASE rendering times! But it can be very useful in some scenes, so keep this in mind as potentially a great tool!

Shadow Softness: Softens the edges of shadows. This will INCREASE rendering times. It too can be very useful depending on what you want to do. If you want to use it, do so at the end of your project to avoid a lot of waiting during test renders.

Visible Object: Will show a small sphere of light as the light source for a radial light, and a cone or bar for spot and parallel lights. This will INCREASE rendering times. It can be useful in some scenes, but apply it last to avoid unwanted waits during test renders.

Visible Object has two options, Surface and Volume.
Surface shows an image of the light source/cone, and takes less rendering time than Volume, which is more three dimensional. This topic is rather complex, so check the Bryce 5 manual for more explanation!

Infinite Light: Extends a light's visible range.

Color: Applies a color chosen from the color pallet to the light source. This has two properties: Uniform and Gradient.
Uniform is a solid color applied to the light.
Gradient can be used to change the color of the light as it travels. If a black/white gradient is used, you can effectively create soft edges on a radial light, or further manipulate a spot or parallel light. Gradient can be a very useful attribute!

Use Gel: Applies a material to the light as a "Gel"-- which works a bit like a colored slide in a slide projector. The Gel can be generated from an image or set as Procedural-- that is, use any Bryce 5 material. The light will "project" this onto surfaces. This gives the light a lot of character.

Falloff: Regulates how a light dissipates or "falls off" as it travels from its source. Light is energy, so of course, it can only go so far until it is exhausted. Think about it. Our Sun is pretty bright to us, but on Jupiter, it is much fainter.

There are four falloff options in Bryce 5:

None: The intensity of the light stays the same regardless of the distance it travels.

Linear: The light gradually dissipates as it travels away from its source. This is the default in Bryce 5.

Squared: The light dissipates rapidly as it gets farther away from its source.

Ranged: The light dissipates rapidly after it travels the distance indicated by the range modifier.

Falloff works in conjunction with Intensity, and we'll be exploring these a lot. They are very useful features!

DO read the Bryce 5 manual on lights. It explains a lot more than I can in the scope of this tutorial! What we will do here is experiment with the Light Lab controls and decide what works best for us for dramatically lighting a scene.

Changing the Lighting in our Scene:
Falloff = Linear

Linear: The light gradually dissipates as it travels away from its source. This is the default in Bryce 5.

As you can see in the NANO preview, the default settings in the Light Lab for our radial light apply a strong light to the scene. By default, Bryce 5 applies a light with Linear Falloff and an Intensity setting of 25.

We're getting good shadows, and the left wall and floor (being lit by the Sun light) are brighter than the other surfaces. There is some degree of shadow in the room corners, but the room looks rather shallow and the whole image is a bit "flat". We can also see a "hot spot" on the back wall and floor. The hot spot can be controlled by the location of the radial light source, but that also affects shadow direction.

Control of linear lighting is done with the Intensity slider.

Lower the Intensity setting in the Light Lab to 10.

The scene simply gets darker, but more of the ambient light of the Sun, and the ambient characteristics of the ceiling light fixture we created allow it to stand out more sharply.

Raise the Intensity setting in the Light Lab to 40.

The scene gets overly bright, The hot spot is prominent and blocks out the ceiling fixture entirely. Objects are brighter and shadows are sharper, but the scene has too much light.

Using a different Falloff method will change things.

Changing the Lighting in our Scene:
Falloff = None

None: The intensity of the light stays the same regardless of the distance it travels.

Set the Intensity back to 25 and change the Falloff to None.

With a Falloff of None, light travels with equal intensity regardless of the distance. So it become much stronger than when a Falloff is applied.

Here it is so intense that it is blocking out the interior environment completely.

Lower the Intensity setting in the Light Lab to 6.

The scene gets is more viewable, and we see hot spots and a little definition of our environment. The look is similar to an Intensity setting of 40 with the Linear Falloff used.

Lower the Intensity setting in the Light Lab to 2.

The scene is much less illuminated and looks similar to an Intensity setting of 10 with the Linear Falloff used.

Play with these features to get more feeling for them. They have very similar effects but rather different settings.

The Bryce 5 manual recommends using a Falloff of None or Linear with outdoor scenes. The strength of the light is advantageous in these scenes, whereas it is not as helpful in an indoor scene.

Changing the Lighting in our Scene:
Falloff = Squared

Squared: The light dissipates rapidly as it gets farther away from its source.

Set the Intensity back to 25 and change the Falloff to Squared.

Squared falloff light dissipates so rapidly that much higher intensity settings are required to get strong illumination. However, this type of falloff allows much more subtle changes in illumination.

At this setting, our scene is similar to the scene with an Intensity setting of 10 with the Linear Falloff used.

If you look closely, you'll see that environmental shadows are more dramatic than with linear falloff.

Raise the Intensity setting in the Light Lab to 50.

The scene gets only slightly brighter even though the intensity of the light source has doubled. Squared falloff has a very large Intensity range with subtle changes. This scene is still similar to the one with an Intensity setting of 10 with the Linear Falloff used.

But, if you look closely, you'll see that environmental shadows are more dramatic than with linear falloff.

Raise the Intensity setting in the Light Lab to 150.

The scene gets much brighter but the intensity of the light source has been tripled from the previous experiment. This scene is similar to the one with an Intensity setting of 25 with the Linear Falloff used.

The shadows in the environment itself (the room corners) have more depth. This makes the scene a little more interesting than when the linear falloff was used.

Changing the Lighting in our Scene:
Falloff = Ranged

Ranged: The light dissipates rapidly after it travels the distance indicated by the range modifier.

In the Light Lab, set the Intensity Value to 10 and set the Range Value to 40.

Ranged Falloff is very flexible and uses two controls to manage a single light source; an Intensity Value and a Range Value.

The Intensity value sets the strength of the light source.

The Range value represents the distance from the center of the light source to the point where the light falls off sharply. It is roughly equivalent to Bryce Units. This distance represents the diameter of the sphere of light before falloff. In a case where the Range is set to 40, the radius of the light sphere is 20 units, or the light shines in all directions for about 20 units before falling off rapidly. Think of an invisible sphere that has a diameter of 40 units. The light will shine within that invisible sphere, and the drop off sharply outside it.

Our scene shows no lighting effect on the environment from our radial light. It won't because the walls of the environment are beyond the range we specified for the light's falloff.

Our red cube object is a different matter. It IS affected by the radial light because its top is within the light's range before it falloff. So we see the top of the cube illuminated.

Keep the Intensity Value at 10 and change the Range Value to 50

We see a hot spot forming on the back wall and the floor beneath the red cube and also on the ceiling around the ceiling fixture.

By expanding the range we are increasing the light sphere.

We're going to discover something interesting as we continue this process.

Keep the Intensity Value at 10 and change the Range Value to 60

The hot spot is now getting prominent. If you've worked with spot lights, this should look familiar! Using a Ranged falloff allows a radial light to look like an omnidirectional spot light!

Our scene now looks a lot more interesting because it appears that the ceiling fixture is casting light like we would see it do in the natural world, washing light across the ceiling as well as casting it into the room.

The red cube is casting a shadow, but not the other objects. That's because they are still beyond the light's range.

Keep the Intensity Value at 10 and change the Range Value to 70

The hot spot is more prominent, and all the objects are coming under the influence of the radial light. But the range is still not enough for all of them to cast shadows. Notice how dramatic the scene looks compared to linear or squared lighting!

Keep the Intensity Value at 10 and change the Range Value to 80

The hot spot is beginning to wash the walls of the environment in places and our objects are casting shadows.

What would happen if we used a higher Intensity value?

Set the Intensity Value to 25 and set the Range Value to 40

The scene is exactly the same as when the Intensity was 10. Most of the scene is outside the range of the light.

Keep the Intensity Value at 25 and change the Range Value to 50

We see a hot spot forming on the back wall and the floor beneath the red cube and also on the ceiling around the ceiling fixture. It is stronger because the light Intensity has been increased. But the distance of the light is still controlled by the Range value.

Keep the Intensity Value at 25 and change the Range Value to 60

The hot spot is now quite prominent.

The Intensity value is high enough to make our ceiling fixture look weak, as if more light is coming from it than it actually contains!

The red cube is casting a shadow, but not the other objects. That's because they are still beyond the light's range.

Keep the Intensity Value at 25 and change the Range Value to 70

The hot spot is more prominent. And all the objects are coming under the influence of the radial light. But the range is still not enough for all of them to cast shadows. The ceiling fixture is impossible to see because the Intensity of the light is so strong.

Keep the Intensity Value at 25 and change the Range Value to 80

There really is too much light intensity in this scene, isn't there? When using Ranged Falloff, the light's Intensity value becomes extremely important!

Considerations with Ranged Falloff:

Ranged Falloff can be one of the most dramatic artificial light controls values in Bryce 5. It is a balance between the Intensity of the light source and the distance of objects from that source... the Range

We only used one light for this tutorial, and we were able to used Ranged Falloff to make the light look like it might in the real world, spreading a wash across the ceiling and on the environment. Of course, in a complex scene we'd use more lights and refine this process.

The important thing to remember about ranged falloff is that as you make the range larger, the SPHERE of light increases. As you change the Intensity, the AMOUNT of light increases within that sphere. This principle applies to other lights as well.

Changing the Lighting in our Scene:
Falloff = Ranged with Ambient Sun Light

So far we've kept the Sun in a fixed position so we can concentrate on artificial light effects. But now let's see how the Sun's ambient light can affect our scenes.

I like the scene with a radial light Intensity of 10 and Ranged Falloff of 80 for this experiment. You can use anything you like, but my example will use those settings.

We'll now switch back to the Sky Lab and work there. So set your light in the Light Lab, then go to the Sky Lab. Be sure to turn on the "Render in Scene" and "Fast Preview" in the Sky Lab.

We've had the Sun set to Azimuth 90 (the right side of the scene) and Altitude 45.

This caused ambient light to influence the left side and floor of our environment and the left side and tops of our objects.

The ambient light is combining with the radial light, so these surfaces look brighter than the others.

Keep the Azimuth at 90 and change the Altitude to 90

The Ambient light now influences only the floor and tops of objects because it is shining down on them.

But, we see light on the right side of our sphere. Why?

Well, that light influence is coming from our radial light, not our ambient light!

Keep the Azimuth at 90 and change the Altitude to 1

The Ambient light now influences only the left side of the scene. So the left wall is brighter because it has the combined illumination of the radial light and the Sun.

Bryce lighting is cumulative!

Change the Azimuth to 180 and change the Altitude to 45

We can see that the ambient light of the Sun is coming from behind the camera and bouncing off the wall in front of us, adding to the radial light. The wall almost looks like a screen. The corner shadows that came from the radial light are being filled in by the ambient light.

And because the altitude of the Sun is 45, we're seeing ambient light striking the floor and tops of our objects and adding to the radial light.

Keep the Azimuth at 180 and change the Altitude to 1

The Ambient light now influences only the far wall of the scene, making it very prominent because the light is coming from directly behind the camera and hitting the far wall straight on. It adds to the radial light, so the corner shadows are not prominent.

Change the Azimuth to 0 and keep the Altitude at 1

The ambient light of the Sun is now showing no influence. It is coming directly towards the camera, so it is bouncing off the wall (and objects if there were any) behind the camera.

So what we see is the scene as if there were no ambient Sun light.

Considerations with Ambient Sun/Moon light:

The ambient light of the Sun and Moon will affect an interior scene just as it will affect an exterior scene. So it can be a useful additional light source augmenting artificial lighting. If you don't want that influence, you can Disable Sun Light in the Sky Lab.

So far we've looked at a simple interior where everything is the same color because we're inside a cube. Normal interiors are not so simple. Walls have colors, ceilings have colors and textures, floors have rugs, and so on.

To add these features to the scene, you could simply create several 2-D planes and apply a materials to them, then position them so they are just inside the "room". The ambient lighting of the Sun will still affect the interior of the scene for you. Using 2-D planes for this approach (instead of 3-D objects, like cubes) simplifies things for Bryce 5. Adding windows will let the Sun light shine into your interior, adding even more effects and compounding shadows!

Bryce 5 is incredibly flexible, there are so many ways to do things!

Next we'll go back to our simple scene and combine Ranged lighting with object Refraction to get even more effects!