shadowgraph tuning indicator

例句：

1. 1. The shadowgraph technique is used tocreate a three-dimensional image on aflat surface.
   影子摄影技术用于在平面上创造三维图像。
2. 2. In the darkroom, photographers use chemicals to develop theirshadowsgraphs.
   在暗室中，摄影师使用化学品来发展他们的阴影图。
3. 3.The shadowgraph was a revolutionary tool forcapturing images in the 19thcentury.
   阴影图是19世纪捕捉图像的革命性工具。