There are a number of celestial features that come into play when Bryce 5 is showing the moon. The folks who made Bryce 5 give us lots of options here! So, we'll explore these and maybe even learn something about how celestial objects work, in the real world and in Bryce 5. We'll use the NANO preview in the Sky Lab, just as we did with the Sun. But, you may have to render your scenes to get a full appreciation of what's happening when working with the Bryce 5 Moon. That's because the moon light is soft in Bryce 5, even at full intensity, and the stars are naturally of different brightness' (Yes, Bryce 5 even figures out the different brightness of the stars!)

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

Setting Up the Sky Lab

1. We'll look at a lot of the Moon effects in the NANO preview of the Sky Lab, but sometimes, because stars are so faint, you may have to leave it and render a scene to see the full effect. Keep your workspace in the Camera view.

2. Enter the Sky Lab and go to the Cloud Cover Section and turn OFF all clouds. We want to see the stars, and the clouds would hinder that. There are however, many Bryce skies with clouds that also show stars. But for our purposes, we'll turn off the clouds.

3. Go to the Sun & Moon section and set things up as follows:

• Celestial = ON
• Random Field = ON
• Stars = ON
• Star Intensity = 100
• Star Amount = 2000
• Comets = ON
• Comet Intensity = 100
• Comet Amount = 10
• Moon Phase = ON
• Earthshine =100
• Softness = 1
• Moon Image = ON
• Sun/Moon Visible = ON
• Disk Intensity = 100
• Disk Glow = 50
• Sun/Moon Size = ON
• Disk Size = 50
• Horizon Illusion = 1
• Sun/Moon Shadows = 50

Manipulate the Moon disk to the left of the Moon Image control so the full face of the moon is showing. We want to see a full moon. There is no way to do this numerically, you'll have to click and drag with the mouse in the moon sphere.

4. In the Sun Control set:

• Azimuth = 180
• Altitude = 0

This puts the Moon in front of the camera and the Sun behind it. You'll see a little moon icon in the Sun Controls to indicate you are looking at the Moon and your scene in the NANO preview should look like the one in the image on the upper left of this table.

You should see a half moon peeking on the horizon. But you can't see any stars yet. The ambient sky light from the setting Sun is overpowering them. Notice that the objects in our scene are lit from behind the camera just as we would expect because the Sun is behind us, the Moon ahead.

Some Celestial Considerations...

Bryce 5 has some unique celestial controls. Here's what they mean:

Celestial:
This turns stars and comets ON or OFF. No matter what setting you give them independently, this control must be ON for them to take effect.

Random Field:
Bryce will generate an "imaginary" star field. Clicking this several times generates different random star fields. Comets will also appear if they are turned ON. The spherical control below "Celestial" will move the star field AND comets around in your sky.

Custom Field:
Bryce 5 will generate a star field as seen from Earth. The spherical control below "Celestial" will display the sky from different locations on Earth. If you know your constellations, you'll recognize them as you move this control. There are no numerical coordinates for this control, you have to move it like a trackball and check for the results. Comets will NOT display when the custom field option is used.

Comets:
These display ONLY when the Random Field option is used. The Bryce 5 manual recommends using a low figure for the amount of comets. That's because they are relatively rare. The spherical control below "Celestial" can be used to change the direction of the comets' tails. To use this realistically, you have to know something about comets.

A comet is "dirty ice ball" hurtling through space. It usually consists of trapped gas, ice and rocks. As a comet passes close to the Sun, the heat of the Sun melts some of the ice. This releases gas and ice particles and debris. That makes the comet glow and gives it a "tail".

But a comet's tail does not follow the direction of the comet's movement! Because of the "solar winds", radiation from the Sun itself, this tail is pushed away from the comet opposite the Sun, no matter what direction the comet is traveling in. The tail faces AWAY from the Sun. So, comet tails are much like Sun shadows, they ALWAYS point AWAY from the Sun.

There are times, such as when you make the Moon a half moon or a quarter moon, when you need to compromise in Bryce 5. You may need the Sun/Moon in a position that would make the comet tails naturally flow away from the camera (and thus not be seen) for lighting purposes, but want to see the comet tails in your scene trailing either left or right.

At these times, the spherical "trackball" in the Celestial section will help because as you move it, it changes the directions of the comet tails. But it also changes the star field. Since it only works in a random star field this may not be of much concern to you.

At other times though, if you do not adjust this trackball, Bryce 5 will align comet tails according to the natural world for you!

The Rising Moon!

Keep the Moon's Azimuth at 180 and set the Altitude to -10 (minus 10) NOTE: ALL Altitudes for the Moon are negative values!

The moon is visible and just off the horizon. We didn't alter the disk size, so it may be a bit large to be realistic. Notice that in Bryce 5 the moon disk, even at full intensity has a purplish tone to it. Things like the "harvest moon" and other very bright moon effects that we see in the natural world are not easily achievable with the default Bryce 5 moon. However, we have a workaround that is the subject of another tutorial, so there is a solution.

You can probably just make out the objects of your scene. Right now there is very little light, so they are very faint.

If you render the scene you may see some faint stars and a comet or two. As the night progresses, these will become more visible. Bryce 5 is very good at rendering actual sky effects, so we're still looking at a twilight type of scene.

The Moon Rising More 1

Stay in the Sky Lab and keep the Moon's Azimuth at 180 but change the Altitude to -30 (minus 30).

We can now clearly see a comet and tail in the NANO preview. Because I adjusted the celestial sphere, the tail is pointing to the left. I simply did that so you could see it. If I had not done this, Bryce 5 would have calculated the position of the Sun and directed the tail opposite it.

The moon, of course has risen out of camera view.

If you render your scene, you'll see that the objects are a little brighter than when the moon was first rising. So in Bryce 5, the Sun and Moon light are controlled by the Sun Controls with similar results. Except the moon light is much less intense than Sun light, of course.

Stay in the Sky Lab and keep the Moon's Azimuth at 180 but change the Altitude to -60 (minus 60).

You'll notice that the comet tail has changed direction. Bryce 5 is maintaining it's relationship to the Sun based on what I artificially established. The Sun is below the earth, shining on the "bottom" of it, so of course, the comet tail is leaning away from the earth.

The moon is getting much more light from the Sun now, so objects are being illuminated more.

Stay in the Sky Lab and keep the Moon's Azimuth at 180 but change the Altitude to -90 (minus 90).

The comet tail is still pointing away from the Sun, and our objects and their shadows are behaving as they did in the Sun tutorial at High Noon, only this time illuminated by the moon light.

And when the altitude of the Moon is at -90 (minus 90), the moon is essentially at the "pole" of the earth. It cannot rise any higher. To continue the moon travel, we must change the Azimuth and then lower the altitude.

Moon altitudes can go from zero (0) to minus 90 (-90).

Lowering the Moon 1

We want to see what happens when the Moon sets behind us. So we have to change the Azimuth to continue.

Stay in the Sky Lab and set the Moon's the Azimuth to 0 and change the Altitude to -60 (minus 60)

You can see in the Sun Controls that the moon indicator is moving down the "sphere" in the Sun controls.

The comet tails really haven't changed much because their relationship to the sun is pretty much the same as it was before.

The sky is getting lighter and out scene is being lit by the moon from behind.

Lowering the Moon 2

Stay in the Sky Lab and set the Moon's the Azimuth to 0 and change the Altitude to -30 (minus 30)

You can see in the Sun Controls that the moon indicator almost at the bottom of the "sphere" in the Sun controls.

The comet and stars are very hard to see now. That's because the Sun is close to rising. But the moon is affecting our objects, just as the Sun did in Sun set. In a way this is a kind of "moon dusk" that we are observing.

MoonSet !

Stay in the Sky Lab and keep the Moon's Azimuth at 0 but change the Altitude to -10 (minus 10).

The moons light is much fainter than the Sun's. So at this point, it isn't illuminating the objects in our scene nearly as well as the Sun did when it was setting. Instead, the light of dawn from the Sun, still below the horizon, is affecting the scene.

The atmosphere is glowing with the dawning light, blocking them out.

Dawn All Over Again!

Stay in the Sky Lab and keep the Moon's Azimuth at 0 but change the Altitude to zero (0)

Bryce thinks it is still night time (see the little moon icon in the Sun Controls?). But it is almost exactly the same as the scene we had in the SUN tutorial when we started. Except, we did turn off the clouds so we could see the stars.

Our object and scene are lit exactly the same though. If you change the Altitude to 1, the scene will look the same, but the Sun Controls will display a little SUN icon to indicate it is now daytime.

In Conclusion...

The Moon tutorial has shown you step by step how the Sun Controls, Azimuth and Altitude work with the Moon. Moon altitudes are ALWAYS negative numbers. It may seem confusing at first. Play with it. Try different settings and see what happens. Eventually, you'll get that "great AHA!" and then you'll own it forever. Just remember that the Sun Control always shows the position of the Sun or Moon from the TOP of a scene, and the Moon's Altitude can never be greater than -90 (minus 90).

The Moon in Bryce 5 is a powerful lighting element!

• It almost always displays a bit purplish and does not have a great deal of brightness.
• It's always opposite the Sun.
• The Earthshine and moon phase controls affect the appearance of the Bryce 5 moon and allow you to put the moon into phases. Other celestial controls allow you to compensate for this, as in the direction of comet tails.

Bryce 5 gives us comets and stars and a way to control them. But most importantly for lighting, the Moon and Sun work the same way in Bryce 5, only the Moon casts a fainter light.

We'll use some of these lighting effects we learned from the Sun and Moon in the tutorial, Artificial Lighting in Bryce 5 - Radial Lights!

But first, let's look at the other sources of Ambient light provided by Bryce 5!