Temperamental Lighting Problem

Hi,
I have a lighting problem in my scene:
I have an earth model (several nested spheres with different images unwrapped on them), as well as a sphere weakly emitting far away (to provide the visual sun in the render), and a sun lamp to provide the real lighting of the earth.

Here’s the problem: whenever the sun lamp is rotated to within ~45 degrees above or below horizontal, the earth is unlit, then there are a couple degrees where it fades in, and outside that range it’s full brightness. I’m working in cycles, and observed this when in render view, as well as when I actually rendered a frame.

Any ideas? If I haven’t given enough detail, please let me know.

Thanks!

It’s a bit unclear, but my best guess is that the sun lamp is rotated such that is is acting strong as a rim light, that is it is coming from behind the earth towards the camera. Have a look at the suns rotation from different angles.

Beyond that provide screenshot(s) showing what’s going on, and of the course posting the blend file will give you a real answer.

I figured it out. Just a silly mistake in some of my settings.http://blenderartists.org/forum/images/icons/icon11.png Sorry about the unnecessary question.

You may be surprised, but few more people can make the same mistake you did. Instead of saying: “Never mind, I solved it” it’d be better to explain to us what the issue was and how you figured the solution out.

yes, as well as clarifying the initial issue. Unlike Cycles, forums are bi-directional :wink:

You may be surprised, but few more people can make the same mistake you did. Instead of saying: “Never mind, I solved it” it’d be better to explain to us what the issue was and how you figured the solution out.

You have a good point. Sorry about that.

It had to do with something which I thought was irrelevant when I was describing my scene. I had a background image on a cylinder that encircled my earth model on the z axis. At that time I hadn’t yet realized that sun lamps are technically infinitely far away from the scene, so the cylinder was actually blocking the light whenever I angled the lamp (which was “placed” inside the cylinder) to shallowly. I fixed it by simply unchecking “shadow” in the cylinder’s ray visibility settings, so it could no longer block the light. There’s probably a cleaner fix, but this worked fine for me.