Question about hidden materials

[rfollett]

I am trying to render and interior scene but my lighting skills are poor.
If I remove the ceiling then scene is ok because it is light from environment GI.. But I need to show ceiling in the render but still have light from GI.. Is this possible?

Thanks Richard

[ValeroStudio]

Re: Question about hidden materials

You should never have to remove the ceiling to light an interior! Thats a no no. My quick 2 cents:

1. Adjust you physical camera settings to let the light burn into the 'film'. This is just how it would be in the real world. You would have to set your exposure time to something like 1/30 - 1/60 with an F Stop of 8. An EV table is a very useful resource. http://en.wikipedia.org/wiki/Exposure_value

2. Add a large VRay Rectangular light behind the camera, pointing into the scene. This is a cheat and is avoided by the pros, but it will light your scene up. Turn off affect specular and reflection. Give a slight warm color and play with the intensity setting. This is how the arch interior photogs light their scenes.. well kinda.

3. In the real world you wouldnt have a space just lit from the window light (typically). Add some lights to your scene.

3. Purchase the latest video of the webinar that Fernando hosted. Its a webinar on interiors and its full of really great tips.

[Micha_cg]

Re: Question about hidden materials

I am trying to render and interior scene but my lighting skills are poor.
If I remove the ceiling then scene is ok because it is light from environment GI.. But I need to show ceiling in the render but still have light from GI.. Is this possible?

Also this is possible, but could be a little bit unreal looking. What you need is a twosided material with a material at the backside only and no material at the outside (normal of the surface can be flipped per _dir and should show outward (front side)). If no material is at the front side light can go through. The backside with material is visible. So you can render a topview and look in the room too. If you use a material for the front side and no material for the back, than you can look through the surface without like can go through.

Here more infos:
http://forum.asgvis.com/index.php?topic=3782.0

[andrewsailmalta]

Question about hidden lights

none of the lights on sketchup vray want to switch on for me. can anyone tell me what i might have wrong pls?

[Pyroluna]

Re: Question about hidden materials

andrew it's probably either the Power of those ligths, or the Exposure of your camera.
if the power is too low (compared with the sky brightness or with camera settings or both), they won't be significant.