The following tip was sent to list HQ: "Forum members might be interested in an item published at www.instructables.com on using a lens, usually installed in doors to allow owners to view visitors, in conjunction with a cell phone camera." Or, you can see the same thing I made for an SLR, probably in the 1980s, and suggested by others at an even earlier date!! My hint without words is at: andpph.com/2016-pix/thru-door-viewer-based-fisheye-1.jpg Andy
