If you provide the main window’s physical width and its distance from your face (both in centimeters), Curved Spaces will provide pixel-perfect perspective. That is, you will see exactly what you would see if you were living in the given finite universe.
You may wish to overreport the window’s width and/or underreport its distance from your face for a wide-angle view. Conversely, you may underreport the width and/or overreport the distance for a telephoto view. Either way, for monoscopic 3D all that matters is the ratio
not the two quantities individually. In practice the wide-angle effect works best, because it compensates for the relatively small size of most computer monitors and shows you a satisfyingly wide portion of the scene. Curved Spaces’ default settings provide a wide-angle effect with a 90° field-of-view.