How to working with Bryce 7.1 pro of Sun&Moon/Light Lab

navalarch2

Hi all,

I am a new user of Bryce 7.1 pro from Malaysia, here I have some questions regarding Sun/Moon & Light Lab to ask you.

How and what I need to do to get a sense of the situation as in the attached reference images.

Chohole

What exactly is it that you are wanting to do?

Horo

navalarch2 - welcome to this forum and to Bryce. I could write a book about the Sky Lab, there are so many possibilities. It is hard to give you a tip without knowing what exactly you wish to accomplish.

Rashad Carter

Looks as if he/she is trying to create an overcast sky with a thick haze atmosphere. As Horo states there are several ways to go about this. So at this point I'd ask two questions:

1. How do you want to light the scene? Do you want to use True Ambience, IBL, or Dome / 3D Fill Lights. Essentially IBL and Dome/3D Fill Lights are similar in function but True Ambience rather different from the other two approaches.

2. What scaling factor are you working to? Bryce does not use typical units of inches and meters, therefore one has to know what scale they are working to. How many BU (Bryce Units) are equal to 1 foot, and so on. Once you know this you can easily determine how your distance haze should build up.

Even without answers to these questions I can begin to give you some ideas of things you can try.

Lighting- You can create an overcast look to the sky in a number of ways. Here are four possibilities

1. IBL- For an overcast sky you will want to use a WhiteSphere HDRI. It is literally what it's name suggests, a fully white image, and it will send light into the scene from all angles with a even distribution of illumination and shading lacking any real directional bias, which is exactly what we want for an overcast type of day. My suggestion would be to disable the shadow casting for the ground plane if there is one, to allow the IBL light to arrive onto the undersides of the target models. Horo makes a whitesphere hdri available on his website if I'm not mistaken. But its also easy to make your own. Just create and save out a fully white image at even the tinitest resolution of 50x100 pixels as a ,hdr format and you're in business

2. IBL from Skylab - You can easily import one of the included sky presets that has the moody overcast look that you want. You can then convert this sky into an hdri that Bryce can then use to illuminate the scene. In many ways this step of searching for an appropriate sky preset is going to be necessary anyhow just to get the look you are after. But again, the appearance of the sky backdrop and the lighting we see in the scene are not required to relate to one another directly unless you decide for them to.

3. A Dome Light is essentially the same function as an HDRi, the only different being that anIBL can assign many colors but a Dome can only be a single color. For the case of an overcastsky a dome with a single color of gray or white will be perfect. There is a setting in the Light Lab to flag the Dome as "Infinite" which makes the Dome as large as the hidden IBL Dome. Thus a whitepshere HDRi and a Light Dome are exactly equal. As suggested above, I would disable the shadow casting of the ground plane of you have one. But it can be tricky to avoid long render times when using IBL and Domes in the presence of water planes and slabs, sometimes it helps to excluse the water materials from the influence of the IBL and Domes. More on that if you have any further questions.

4. True Ambience is Bryce's implementation of a Global Illumination algorithm. It requires some degree of understandign and experience to get the exact results you woudl want. There are also several techniques for using True Ambience. One of the specialized approaches I like was developed by David Brinnen and Horo called Obscure Light. It does a very good job of providing indirect light shading on complex models, perfect for overcast days like the one you appear to be seeking. but again this is an entire lesson on its own. there are youtube videos on Obscure Light if you have the time and the interest.

Based on your feedback we can hopefully cater advice to better suit your direct needs. All the best!