Runco Reflection CL-610 CineWide Owner's Operating Manual page 40

Installation
To avoid clipping the corners of the image, position the anamorphic
Tip
lens as close as possible to the primary lens.
There may be some pincushion distortion even after the lens is
Note
properly adjusted, especially at shorter throw distances. If this is the
case, Runco recommends that you slightly over-scan the image
into the screen frame area to mask the distortion.
28 Runco CL-610 Series Owner's Operating Manual