A homemade pinhole cap (with filter glued on the front so dust would not get inside the lens mount and reach the sensor).
Instead of making the area of view wider with the fisheye adapter, it made it much smaller as if looking through a doors peep-hole.
The softness was an interesting outcome. Aren't pinhole images supposed to have a huge depth of field where everything is in focus? Research indicates this is what happens when the element of digital is introduced to pinhole photography, and diffraction is the culprit.
For more on the diffraction/pinhole/digital issue, refer HERE and HERE.