I am currently having some trouble with various renderpasses in my rendering process. I have a model that has a large glass sphere in it with other objects behind it. These objects however do not fill the entire sphere, and I want the rest of the sphere to be transparant in the output (Alpha + PNG). Now, for the Beauty pass, this works perfectly fine. But as soon as I add other passes such as Ambient Occlusion or any of the other render passes, the output files do not have transparency for the glass sphere.
I could of course disable the glass sphere for rendering all the other passes, but the sphere has a high IOR. This results in the passes not being refracted properly and not aligning up with the original render for compositing in Photoshop.
Does anyone have an idea how I could fix this while still keeping my render output file transparant? Or am I forced to render with a background?
I do unfortunately not know how you can fix this in Visualize, but I have another suggestion to make the sphere background transperent.
Maybe it could work if you add a non-used coloured item right behind your glass sphere as a "background" for the sphere. For example a very saturated magenta. When you then import the rendering intro Photoshop, you can go "Select" -> "Colour Range..." and then select the magenta colour, decide the fuzziness to fit the picture and either delete the colour or create a mask to cover it.
Let me know if you figured out how to fix it in Visualize.