Perspective vs orthographic lens: Background technique?

Scripting Issues
1

Until know I had a perspective lens in my game. However, things always looked a bit unnatural since I am going for a 2.5D (2D?) look. With the perspective lens this technique for creating a background always worked:

background = loader.loadModel("../gfx/invertedsphere")
	background.reparentTo(camera)
	background.setHpr(0,0,0)
	background.setBin("background", 10)
	background.setDepthWrite(False)
	background.setDepthTest(False)
	background.setLightOff()
	background.setShaderOff()

Nothing unusual as far as I know.

Switching to an orthographic lens the background model is now an isolated ball in the middle of a default grey background.

What do I have to change to make this technique work with an orthographic lens, too?

2

Increase the scale on the sphere, just enough to envelop the film size of your camera.