From Wayne Faszer:

 Film degrader has the following film thicknesses,
 made up of layers of mylar and/or kapton.
 Position    Thickness(thou)
    1            0.0
    2            0.5
    3            1.0
    4            2.0
    5            3.0
    6            4.0
    7            5.0
    8           10.0
    9           20.0
   10           40.0