Ed Majden posted:

Does anyone know what happend to Dr. Henry Paul's solar prominence
filter as described in the ATM series of books, Book Three, I think.

I don't know what happened to the unit he built, but there were undoubtedly
others.

It was
made of a stack of quartz plates of various thicknesses. I wonder how this
type of device compares to modern day interference filters? I believe this
was called a Lyot Quartz Monochromator.

They can be as broad or also as narrow as the Fabry-Perot Etalon-based filters
used today. It depends on the number of elements you want to put in (the more
elements, the narrower the passband generally is). It is a somewhat more
complex design than the F-P filters, but if you can get access to the quality
quartz (not an easy task BTW), as well as the interspaced polarizers, you
could make one yourself. Clear skies to you.
--
David W. Knisely
Prairie Astronomy Club: http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/

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