How do skydomes work?

Drogo Nazhur

Whenever I load a scene with a skydome in it, the rendering come out complete black. If I remove the skydome, the scene comes out looking correct (minus the sky, of course). What am I doing wrong?

mjc1016

What renderer are you using?

If you are using Iray and loading a skydome, chances are, it was set up for 3Delight.  If that's the case, it will actually act like a giant umbrella and block all light from reaching the scene.

Drogo Nazhur

Yes, I use Iray -- I like the way that Iray renderings come out better.

Is there a way to use Iray and still light up the scene WITHOUT overcomplicating things too much?

mjc1016

If the skydome has an hdri associated with it, then it may be possible to plug that into the Iray dome (it's under Envrionment in Render Settings) and use that for lighting.  The one problem is, many of the skydomes for 3DL used a jpg for placing on the dome itself and lo-rez/pre-blurred hdr or tdl image for lighting.  While the hdr images would work for lighting in Iray, they won't be usable as a backdrop.  The higher resolution/detail jpg isn't suitable for using for lighting in Iray.

There is a thread, linked to in my signature, that lists many HDRIs suitable for using in Iray.  Many of them I have indicated if they are just usable for lighting or can also be used for backdrops.  For 'quick and easy', especially for 'exteriors' it doesn't get much easier...drop the image into the map slot and rotate (yeah, you'll need to test render to check, but even a few iterations will show general lighting cues).