I have the same question, but need to insert a 3d object in a 2d photo using Octane Standalone (no C4D).
I have a camera matched project fom Sketchup,
Exported Cameras with Tig OctaneOCMbatchExporter.rb (Awesome)
But I can only use hdr backgrounds and any photo I try to insert as TEXTURE ENVIRONMENT is processed as spherical or cubic, losing the camera match.
Can anyone help me?
I would also need to lock the camera