Oh, wait... if you have only one shadowcam, you can just remove it
easily from the PZ3, and then you'll have a perfectly lightless scene
to start from. 

Look for

camera SHADOW_CAM_LITE
    {
    name    Shadow Lite 2 Cam
    off
  ........
   
then scroll down to the end of that bracketed paragraph and delete it.

There will also be a short paragraph referring to the OBJ file
for the shadowcam

camera SHADOW_CAM_LITE2
    {
    storageOffset 0 0 0
    objFileGeom 0 0 :Runtime:geometries:Camera:Camera.obj
    }

but you don't need to remove that if you're uncomfortable with
deleting stuff.  Poser is already loading Camera.obj for the
real cams, so it won't hurt to load it again.

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