Entry for EPT 2024 Photo Competition. Title: Blowing out a candle - Visualising heat waves with Schlieren photography
Time series (left to right) showing blow out of a candle flame. Due to the difference in the refractive index of heated gas, the heat waves can be visualised by Schlieren photography. Light from a point source is aimed towards a spherical mirror which focuses the light back to a point, where a knife edge is placed to cut out undistorted light. In this way, any changes in the density caused by the candle, placed between the light and the mirror, appear as a sharp contrast (red/black) in the image due to refraction. Photo: Eirik Æsøy/NTNU
Entry for EPT 2024 Photo Competition. Title: Blowing out a candle - Visualising heat waves with Schlieren photography
Time series (left to right) showing blow out of a candle flame. Due to the difference in the refractive index of heated gas, the heat waves can be visualised by Schlieren photography. Light from a point source is aimed towards a spherical mirror which focuses the light back to a point, where a knife edge is placed to cut out undistorted light. In this way, any changes in the density caused by the candle, placed between the light and the mirror, appear as a sharp contrast (red/black) in the image due to refraction. Photo: Eirik Æsøy/NTNU