How can I make this shadow disappear?

Support Materials and Textures
1

I have the following node setup for an emission plane. As you can see, I made the object invisible from the camera and I also unchecked everything except Diffuse in “Ray Visibility”. It does what I need, except it leaves a shadow. How can I get rid of the shadow on the ceiling?

2

Try this:

111111111.png762×569 55 KB

Nope… wrong :no:

3

You are using the wrong tool for the job in my opinion, no offense meant. You want to use an area light for this application. Remember to check the multiple sample box.


Although I think it looks quite unnatural, and the ceiling loses its solidity, because the light has to come from somewhere, right?
If you have access to the light falloff node you could give it some smoothing to kill some glare on the wall.
To get a really even all around light box effect, you might want to use the invisible wall setup I use the light path node for. When using an actual camera and a light tent I used to have to make a little hole for the camera to look in through. Not any more!

Attachments

lightroom.zip (132 KB)

4

Hi @sillytoon. Just two things:

  • Add a Transparent node (color 1,1,1) to the empty input shader in your setup
  • Maybe your meshlight is showing its back face. Then rotate it 180 degrees

I use something similar in the light setup of my lightbox.