![]() The spectacle-shaped viewers may be too large to be worn securely by some children. Any black and white film negatives bearing images.Materials that should not be used as solar filters include: A shade number 12, 13, or 14 welder's filter can also be used. If you do choose to use a viewer, always follow the manufacturer's advice. Which design you use is a matter of personal preference, but viewers bearing the "CE" mark from Europe may be more safe. The filter material is usually mounted in a cardboard frame that can be worn on the head like eyeglasses, or held by hand in front of the eyes. Special eclipse viewers made of either aluminised polyester or a very dark polymer material are available but these cannot be guaranteed to be totally safe. ![]() Viewing the partial eclipse in London in 1954 - how not to do it
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