Unsafe Solar Filters on EBay

I though these things were gone!

Eyepiece mounted solar filter
DO NOT USE! A Solar filter meant to thread into a 0.956″ telescope eyepiece.
But no, in the world of cheap e-commerce, any product can be found, even those that are notably unsafe.

What are we discussing? Eyepiece style solar filters that screw into the threads on the bottom of the eyepiece, not at the front of the telescope like proper solar filters.

I actually have one of these things, found in a kit of equipment I was given. A bright red and very cheap pot metal casting with a small glass filter. I have never attempted to actually use it, I keep it as a example of the bad and the ugly. It is a vintage bit of gear, the type that was included with inexpensive Japanese refractors of the 60’s and 70’s, sized to be used with the small 0.965″ eyepieces of the era.

An eyepiece style solar filter available on EBay
An eyepiece style solar filter available on EBay
To my surprise I find out these things are still around… I was shopping for an inexpensive solar filter for a small telescope when I came across these eyepiece style filters on EBay. They are cheap too, less than $10 with shipping, just the sort of thing to attract a young or novice telescope user into trying a product that is potentially very dangerous.

Given that the risk you are taking involves irreplaceable eyesight, this is very serious.

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