There's more to period costume design than figuring out the patterns. “Today’s fabrics often don’t work in other time periods,” explains costume designer Kimberly Adams in a fascinating story at Smithsonian.com. “The weights, textures and content are quite different, and these factors really do make a difference in making a costume look true to a time period.” The piece profiles Thistle Hill Weavers, which specializes in creating historically accurate textiles, spinning the thread and weaving the fabric on 100-year-old power looms.

The company, started by a textile historian and weaver by the appropriately 18th-century-sounding name of Rabbit Goody, has made fabrics for such productions as There Will Be Blood, Road to Perdition, and The Curious Case of Benjamin Button.

You'd think living museums such as Colonial Williamsburg might be most concerned about making sure costumes and fabrics look genuine close-up, but in fact it's more vital on screen: “The camera eye is better than any human eye so inaccuracies show up glaringly,” explains Goody. “The minute anyone sees an inaccuracy in a movie, that picture is trashed — if you don’t believe one part of it, you’re not going to believe any part of it. A lay person may not know what would be appropriate for 17th-century fabric, but it will register that something is wrong.”