Blackmagic Forum

Hey guys,

i have a problem with the VolumeFog. Every time i render a WPP Pass with Mental Rays XYZ-Shader in 3ds max and saving this pass as an EXR, the Volume Fog tells me, he does need position information and fails.

I add a Channel Boolean, put the beauty into the BG input, put the WPP EXR into the FG input and extract position X,Y and Z values from the FG image (which is the EXR). i then feed the output of that Channel Boolean to the VolumeFog. And the result is what i written up above: The VolumeFog fails, he tells me, he needs position information and fails.

The WPP pass is rendered as an EXR in 32-Bit Float. I did everything right i guess, but Fusion cannot use that information

What have i done wrong?

Any help would be amazingly appreciated. Im using the non-Commercial version 8 of Fusion.

- Steffen

what are your settings in the channel boolean?

do under the "aux channels":
1)set the operation to "copy"
2)check "enable extra channels"
3)under the x,y,z position choose the channel from the FG input which holds the WPP data

now you can use the color inspector sub view to see if you have any position data in you image:
view the channel boolean in the viewer, enable the sub view, set it to "color inspector". if you now move the mouse over the viewer you see the color values of the image and also the extra channels. if you see values for PX,PY,PZ then your image has position data in it.


maybe you can upload a small example comp with 1 frame of the rendering, so we can have a look at your data