Quality Assurance of Precision Optics: Coating Check

This video, from the National Center for Optics and Photonics Education, demonstrates "quick methods to determine which side of a precision optic is coated, and which colors may be affected by the coating." The video first shows uncoated precision windows, followed by coated precision optics, and note the difference in each reflection. As the video explains, coated precision becomes clear once one notices shadows, or the quality with which colors are reflected.

The video runs 4:55 minutes in length.