Ground plane

[kmwhitt]

Is anyone using a ground plane outside for interior renders?  I know in older versions of Vray it was recommended for additional bounces.  I am wondering if it is even necessary with Corona.  I noticed you can specify a color for the ground which leads me to believe it already handles bounces from an invisible plane.  Thanks!

[kmwhitt]

I'd really appreciate some feedback on this topic.  Anyone on this forum using a ground plane for additional bounces when rendering an interior?

[houska]

What are you actually trying to achieve? What does your scene look like and where would you put that plane exactly?

[kmwhitt]

I thought I was fairly clear.  Is it necessary to place a ground plane outside when rendering an interior, so that you get extra bounces inside the room?  I have tried both and get mixed results.  For instance, if my ground plane has a grass texture, it will cast unwanted green tint inside the room, but I do seem to get more illumination.  However, I can control this with a ray switcher.  I was just wondering what others are doing for their interior renders - ground plane or none.  Further, as Corona Sky has an option for ground color - I wanted to know if Corona is already calculating these additional bounces inside the room.  Thanks for your reply.

[houska]

Aha, now I understand, thanks for clarification. I was confused by the "additional bounces" :-)

I cannot tell you what the others are doing, but in general if you want to simulate light bouncing off the grass, you have to either have that in your sky model (so either the Sky+Sun or an HDRI map) or you have to add a plane for that light (as you were describing). Of course, if you have green grass outside, the reflected light will tint your room green, as it would in reality.

If you use Sky and Sun, you can use the ground color and it will act exactly as if you had a plane of that color outside of the room, exactly as you suspected.

Hope this clears things up

[kmwhitt]

Thanks Houska.  Relying on the sky's ground color is so much easier than bothering with an actual landscape.  I'll just have to keep tweaking the color to get what I'm after.

[houska]

Well, it should be as easy as matching the color tint and albedo using the HSV model. As for the specifica values, I'm afraid you'd need to ask another artist :-)