The Photo idea using a mirror was inspired by Alex and the photos on his website.
The inlays were done to the blank while it was srtaight cut at about .520 Diameter.
I used the Unique Products CueMonster inlay machine designed for inlaying pool cues but adapted to pens.
The inlays are cut to a depth of about .060".
http://www.cuemonster.com/cnc_ii_machine
They also make a manual Pantograph style machine for less money.
Because they are flat bottom inlay pockets and the pen blank is round, the width of the design is limited to about 1/4 inch.