A solar eclipse can be viewed safely using proper techniques, such as by using a pinhole camera, a telescope equipped with a solar filter or by solar projection through a binocular.

 
  • 比如针孔照相机、装配有滤光器的望远镜都可以用作安全观赏日食的工具或者将日光投影图与双筒望远镜配合使用。
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