blender camera with off axis frustum

I would like to render my Blender scenes with an off axis projection, thus I need to set the frustum to the camera.
I only found how to set the camera as projection or ortho, does nayone know how to do that?

cheers gordon

I don’t think you can

you’d probably have to render an oversize image and crop out the part you don’t want
[which, iirc blender can do on its own]