In
the Environment section of the
camera’s Attribute Editor (View
> Camera Attribute Editor), click the Create button
to the right of the Image Plane attribute.
Maya creates an image
plane and connects it to the camera.
Set
the Type attribute for the image
plane to Texture.
Click the texture button for the Texture attribute.
The Create
Render Node window appears.
Select the texture you want to use as
a background (for example, an Environment Texture).
Maya creates the texture
and connects it to the image plane.