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Old 17-11-2005, 09:40 PM
Honk if u luv cheeses...

rochler is offline
Join Date: Nov 2005
Location: Adelaide
Posts: 146
Thumbs down I too had one of these....

EP Solar filters. It came with my first 'Dept. Store' scope (115mm reflector) in the late 60's. I used it a number of times correctly (by putting on the aperture mask so that only a small portion of light entered the OTA and it was o.k.)

However, it is *very* easy to forget to use the aperture mask, particularly for a child (I was only 9 at the time) and on one occasion that is what I did. Luckily I was taking a break & talking to my brother when all of a sudden I heard a loud 'pop' and instantly an extremely bright beam of light emerged from the eyepiece. We were both like 'wow, what is that?' I immediately pointed the scope away from the sun and took out the eyepiece. Examination of the filter showed that it had a huge crack diagonally across the entire surface - it had expanded from the heat to the point where it exploded. Even at that young age I shuddered at the thought of what might have happened to me.

If I had been looking thru the EP at the time I would have instantaneously fried my own lense & optic nerve! I won't even try to imagine the agony it would involve either - it would be mebbe like someone plunging a red-hot dagger in your eye? I would undoubtably be blind today, but for sheer luck.

These EP filters *can* work safely *but* only if EXTREME caution is used. But quite rightly, the risk is far too high to allow these to be sold to unsuspecting users. It is not unlike giving a child a loaded .357 magnum on a hair trigger and inviting them to peer down the barrel while they play around with it.....