During the near-total eclipse of the sun in the summer of 1964, my friends and I were warned about the danger of looking at the sun. So we made a version of the camera obscura.
All we did was take a cardboard box, cut out one side completely, cut a part out of the other side or top, place a sheet of paper on the small opening, and punch a pin-hole into it.
The sun is far enough away, and of such a shape, that a perfectly respectable disk was formed. I called it my 'theatre of the sun'.
The father of one of my friends, who was a doctor at the Mine Rescue Station in Elliot Lake, Ontario was so concerned, that he specially overexposed X-ray film, to make us 'smoked glass' filters.
The eclipse was overwhelming. It was about midday, and it was 95% - 98% of total. As the sky darkened, the wind slowed, and the birds—this was the strangest—they became quiet; they obviously thought it nightfall!
Reading about total eclipses is nothing like the actual experience. From that moment, I believed how people could be made afraid by such an event.