Large Buildings and the Mental Ray Sky System

[kyle.sutherland]

Hey all:

This is going to be kind of long as I’ve been doing Max for a little over a year now and I’m still struggling with some lighting concepts in my scenes. I posted this in the area lighting forums also.

Some background:
I work for a structural engineering firm that uses revit for all of our jobs. My company often has me do buildup sequences in 3ds Max Design to produce animations to show our clients. These scenes almost always involve large models of buildings building themselves up or something similar. The way I learned how to start doing this was using the mental ray sky. I typically leave it at the default settings and orient it to best illuminate the scene. The only changes I make is changing the exposure value from 15 to 14.5.

Problem 1:
This problem comes from when I make an animation that circles around the building. Naturally, since the light is coming from a single direction the opposite side of the building is darker due to the shadows. I figure the easiest solution is putting the mental ray sun on the same path as the camera, but I don’t know how to do that. So I’m looking for either how to do that or a better way of doing it.

Problem 2:
This comes from zooming in on section of a building where the interior is meant to be shown OR trying to do a walkthrough. The mental ray sky system seems to be terrible for this. If I try zooming in, everything on the interior is very dark and shadowy. How can I illuminate this better? I’ve tried all kinds of light sources and everything I have done seems to look terrible.

Problem 3:
How can I lower the horizon line? The grayish background tends to wash out a lot of the concrete colors.

This is a youtube video of one of my recent animations http://www.youtube.com/watch?v=7QC-pVHdl9Y. The first 10 seconds or so appears to be buggy but the video illustrates each of the issues I have listed. I would appreciate any commentary with regard to my lighting problems or any feedback in general. This was done in 3ds Max Design 2011.

Thank you

[loydg]

Kyle,

Great work there! Fun stuff animating construction sequences. It can certainly make your head spin trying to get all the data coordinated in the model.

Couple bits of feed back for you:

1) Is the client requesting the circle fly around? For me the circlular motion is distracting the view from the awesome buildout that is happening. It's hard for the viewer to keep up with the camera motion and the animated construction. So, if there is really nothing that is driving the story on the far side of the building, I'd keep the camera on 1-2 sides of the building. I'm not suggesting that you totally bail on the camera moves, just make the much slower and easy for the view to see the buildout.

2) Going with the above suggestion will eliminate having to go around the backside of the building and seeing the "dark side." Trying to animate the sun around with the camera would look weird. Trust me.

3) To brighten up the interior, be sure you have Global Illumination turned on. If that doesn't help, try using an mr Sky Portal to direct some of that sky into the interior.

Keep us posted on the progress!

[ferrimar]

definitely use mr sky portals and animate the Exposure Value (EV).
I hope this helps.