Solar and astrosolar filters

Direct solar observation is very harmful to our eyes if we do not use adequate protection. To avoid greater evils, specific sunscreens have been designed for observation of the sun.
These filters can be attached to eyepieces, telescope objectives, ground-based telescopes, binoculars, and camera lenses. The adaptation varies according to the diameter of the objective to be protected.
Beyond an aid to observation, it is also a tool for astrophotography.