The
suppliers of some cheap refractors supply a welder's
glass filter (pictured left) that screws on to the eyepiece.
DO NOT USE THESE!
They may
heat up and crack as you are looking through the telescope.A
proper solar filter always goes on the
front
end
of the telescope, blocking the sunlight
before
it enters the optical system.
Thanks to the
Orion
Telescope Center
for the loan of this unsafe filter.
Orion does not sell these! They just had one around
as a bad example... They are good and knowledgable people.
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