Phone-O-Scope: Step 6
The slightly odd Phone-O-Scope, which is an adapter to affix SLR lenses to iPhones.
Build instructions and more details are here.
Cut a hole in the lens end cap (inset top left). Use the measurements for the top and bottom cardboard tubes (step 4) to figure out how much you'll need to trim the PVC connectors. The distance that you get from the cardboard tubes should be the same as when the PVC connectors are roughly screwed together halfway, so you get lots of room to move them back and forth. To the top connector, attach the end cap. If you need, cut a notch out of the bottom connector (inset, bottom right) so it fits nicely on the case. Attach the SLR lens just and verify that your measurements are right.