The below video was found on Youtube. It briefly describes the process of making the Outlander tartan specifically for the show. They are even registered with the Tartan Register and you can see them all here.
Outlander Tartan Had Its Own Tartan Made
Written by Helmut Watterott
Did you know Outlander had its own tartan designed and made? Here is a quick video on how it was made.
Slàinte Scotland Tours
Slainte Scotland / Clyde Coast Tourism Ltd
74 Davaar Road