Separate from Background

[devin]

I've been trying to figure out how to separate my buildings from their background and from what I've read it sounds like it might not be possible when using Physical Camera and Sky and when using backburner's split scanline function. So can this be done and if not how do you guy’s work around this?

[mike_kennedy]

Try TGA instead of the format you are using now for split, we ran into the same problem with tiff....not sure what your using but TGA seems to retain alpha when sent via split.

[ShaunDon]

Hey Devin --

Are you using a VRay Dome Light to light your scene? If so, and it's visible, the dome light gets included in the background. The workaround for that is to turn on camera clipping in your VRayCamera and set the far range to as high as it will go. I usually just put the same map or color I'm using in the dome light in the environment color slot as well (under the Rendering --> Environment menu) then make the dome light invisible. Gets painful when switching to multiple cameras, but we use RPManager for multiple cameras in one scene and it handles the settings.

Good luck,
Shaun

[devin]

I am using a dome light so I'll probably have to try it your way but I'm going to give the TGA a shot first.

[ShaunDon]

Mike's right, you'll need to save out a 32-bit TGA file in order to preserve the alpha channel, however if the dome light is set to be visible, you'll get a pure white alpha channel anyway.