Posted on 11/03/2019 6:29:49 PM PST by BenLurkin
Thanks for the warning. I’ve used this same filter to watch Mars transit the sun and I’ve used it to watch a solar eclipse. Go to a welding supply store and ask for the the darkest they have. You can also put on a pair of sunglasses while you’re looking though it.
I have a Questar 3 1/2 inch telescope. Bought it in the late 1960’s. It came with a small 1 1/2 inch solar filter.
I also bought a full-aperture solar filter for it.
Both filters are basically mirrors which screw onto the front of the scope. They reflect 99.99% of the incoming light and transmit the remainder. I might be wrong on the actual number.
You can google “solar filter for Questar 3.5”
I used the filters for the Venus transit some years ago.
You must mean Venus or Mercury transiting the sun. All others have superior (farther than earth) orbits and don’t transit. I suppose you could also take a filter like mine, break it in half, and use both pieces. Still just better to not to risk it. I used to look straight at the sun when I was younger. You can do that if you let your eyes fully adjust first, but it’s just stupid in any case. Luckily, I’ve no holes burned in my retina like some people who do that get.
Yes, you’re right, I made a mistake. Trust me, a number #14 and a pair of sunglasses(though not entirely necessary) will be fine.
That’s a classic scope!
Questar still works fine after more than 50 years!
Thanks BenLurkin.
Using a camera obscura is another possibility.
http://www.freerepublic.com/tag/mercuryintransit/index
http://www.freerepublic.com/tag/potsdamgravitypotato/index
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