This lens was originally designed for Arri SR 16 mm format. It was modified by adding an element on the back to increase its coverage to Super 16 format. The image quality is still there but the added lens causes extreme pincushion distortion at its wide angle range. The T-stop is also increased from its original T2 to T2.5. The adjustable friction attachment engaged with the zoom ring helps the cameraman to perform smooth hand operated zooms. The optomechanix in this lens is so well done.
