Astronomy/Solar filters

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Expert: - 2/22/2005


Question
Can I cover the objective lenses of my binocular with mylar film and use it to view the sun? Are there any specific thickness of film to use?

Answer
Hello.

If it were me, I wouldn't do it - since mylar comes in varieties - advertised as 'mylar' - but not with consistent and necessary filter properties.

I think the best means of solar observing remains the projection method, wherein you use a pinhole type "camera"(bascially a foot long cardboard box, e.g. shoe box, with pin hole in one side) and project the Sun's image at the other end.

Failing that, photographic film (negatives) work - but it MUST be the old black and white type emulsion, doubled over. Not the new 'red' tint sort of film- which offers barely any protection at all.  

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Philip Stahl

Expertise

I have forty years of experience in Astronomy, specifically solar and space physics. My specialties include the physics of solar flares, sunspots, including their effects on Earth and statistics as applied to astronomical investigations.

Experience

Astronomy: more than forty years experience starting with construction of my own simple telescopes. Worked at university observatory in college, doing astrographic measurements. M.Phil. degree in Physics/Solar Physics and more than ten years as researcher.

Organizations
American Astronomical Society (Solar Physics and Dynamical Astronomy divisions), American Mathematical Society, American Geophysical Union

Publications
Solar Physics (journal), The Journal of the Royal Astronomical Society of Canada, The Proceedings of the Meudon Solar Flare Workshop (1986), The Proceedings of the Caribbean Physics Conference (1985). Books: 'Selected Analyses in Solar Flare Plasma Dynamics', 'Physics Notes for Advanced Level'.

Education/Credentials
B.A. Astronomy, M. Phil. Physics

Awards and Honors
American Astronomical Society Studentship Award (1984), Barbados Government Award for Solar Research

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