Mystery Lab / Exhibits & mechanisms
What Appears When the Light Comes On?
Light a hidden ring, then brighten the stage background. Explore how the same reflected figure looks under two changing lighting conditions.
What stage effect is this activity based on?
Pepper’s Ghost is the name of a nineteenth-century stage effect. Light from a hidden object reflected off angled glass, making its image seem to occupy the stage in front of the audience.
Here, an original mint-coloured ring takes the place of a performer. Watch the audience view alongside the apparatus, and change the light on the ring and the background brightness one at a time.
First, turn on the ring light and see whether its image appears in the audience view. Then hold that light steady and brighten only the background. Watch how clearly the ring’s outline stands out.
Continue with the story and its records
Explore how the difference you noticed connects with the surviving records of the historical story.
Read the story of Pepper’s GhostOpen the source
Sources and scope
The historical account draws on the Corning Museum of Glass. The Ontario Science Centre provides the reflection activity and terminology. We also consulted the University of Arizona’s optics outreach guide when designing the model’s lighting conditions.
- 01Ghosts and Magic…and Glass?: Pepper’s Ghost and glass optics Corning Museum of Glass · Checked 2026-10-22
- 02Haunted “Hologram” Ontario Science Centre · Checked 2026-10-22
- 03POPtics Pepper’s Pyramid University of Arizona · Wyant College of Optical Sciences · Checked 2026-10-22
The wording and diagrams are original explanations based on these records. No external photographs or historical illustrations are reproduced. The activity explores how lighting and reflection affect an image; it does not explain every detail of a particular performance or every viewer’s beliefs.