I am trying to add an image as render background in 2.75, using Blender Render, not Cycles. I add a world texture, mapping set to "view". What I want is an image mapped 1:1 to the rendered background, meaning when I render the same dimensions as the input image, I want to get the same image as render output. What I get is an image with a pillow distortion, which amount depends heavily on the focal length/field of view of the camera:
(This uses a rectangular grid as input)
Looks like some kind of spherical projection to me, but I set mapping coordinates to "view". I remember this working in previous Blender versions without having to use the compositor, what am I doing wrong?