Dust Cover
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What is the hole in my telescope's dust cover?
Silly question I guess, but I cannot find the answer. I have a reflecting telescope with a plastic aperture cover, off center from the cover is a hole. I'm mighty curious as to what the purpose of this is!
The telescope is a 114mm Zhumell reflector. The hole in the cover is about two inches in diameter.
This is a hold over from the bad old days when telescopes were supplied with eyepiece solar filters. The idea was to reduce the size of the aperture to lessen the heat reaching the filter, but, even so, the filters got really hot and sometimes cracked, causing blindness. I recommend gluing the two parts of the dust cover together, and never ever looking at the Sun unless you have a proper full-aperture solar filter which blocks the Sun's light before it enters the telescope.
