# Solar eclipses: partial vs totality **URL:** \ **Category:** Factual Questions\ **Created:** [March 20, 2017, 5:55am UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593 "2017-03-20T05:55:32Z")\ **Posts on this page:** 20\ **Page:** 7
**Author:** ![HeyHomie](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heyhomie/32/207_2.png) [@HeyHomie](https://boards.straightdope.com/u/HeyHomie)\ **Post date:** [April 6, 2017, 3:22pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/121 "2017-04-06T15:22:53Z")
I live /just/ outside the path of totality - as in, a few thousand meters. A 40-minute drive north (to Sullivan, Missouri) and I’d be right in the middle of the path. But instead, Mrs. Homie and I are driving about two hours east, to Saint Genevieve, Missouri, to see it. St. Gen is a much prettier town, so we’re going to see the tourist attractions, get some lunch, make a day of it. I live in fear of it being a cloudy/rainy day that day. ---
**Author:** ![TreacherousCretin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/treacherouscretin/32/476_2.png) [@TreacherousCretin](https://boards.straightdope.com/u/TreacherousCretin)\ **Post date:** [April 6, 2017, 8:22pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/122 "2017-04-06T20:22:32Z")
Thanks, folks. The imprecise map answers my questions. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [April 7, 2017, 4:19am UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/123 "2017-04-07T04:19:53Z")
> [@panache45](#): > > That should be “the entire _contiguous_ U.S.” - not all of Alaska. And most of Canada as well. I was wrong. There will be SOME eclipsing in all of North America, Central America, and northern South America. ---
**Author:** ![Iggy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iggy/32/3364_2.png) [@Iggy](https://boards.straightdope.com/u/Iggy)\ **Post date:** [April 7, 2017, 5:13am UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/124 "2017-04-07T05:13:17Z")
Soooooo wanting to get Mrs Iggy a visa to visit the States for this one. But if we cannot she will still have a partial eclipse visible from west central Colombia - the country in South America, not the state capital of South Carolina. The zone of partial visibility will be HUGE. I’ll be in the upstate of South Carolina where the eclipse will pass approx 2:40pm. I need to scout sight lines since mom’s house is surrounded by trees. I _think_ we have enough of a clearing to get good sight lines. I should have a welding visor in the shed if it didn’t get tossed out in a fit of spring cleaning. Time is short so maybe better go ahead and order enough suitable vision shields so everyone has their own. Time is short. No sharing. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [April 7, 2017, 10:05am UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/125 "2017-04-07T10:05:48Z")
> [@Iggy](#): > > Soooooo wanting to get Mrs Iggy a visa to visit the States for this one. But if we cannot she will still have a partial eclipse visible from west central Colombia - the country in South America, not the state capital of South Carolina. > > The zone of partial visibility will be HUGE. [This](https://www.timeanddate.com/eclipse/in/colombia/bogota) is what the eclipse will look like from Bogota. ---
**Author:** ![Bullitt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bullitt/32/5725_2.png) [@Bullitt](https://boards.straightdope.com/u/Bullitt)\ **Post date:** [April 7, 2017, 1:25pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/126 "2017-04-07T13:25:27Z")
The point of greatest eclipse duration will be in southern Illinois, near the small town of Lick Creek. > [@TreacherousCretin](#): > > I don’t think this has been addressed: where can I see a map showing the path of partial eclipse? How far north or south would I have to be not to see any eclipsing? I realize that while the imprecise map gives partial eclipse information for CONUS, it does not fully answer you. This NASA map does, [https://eclipse.gsfc.nasa.gov/SEplot/SEplot2001/SE2017Aug21T.GIF](https://eclipse.gsfc.nasa.gov/SEplot/SEplot2001/SE2017Aug21T.GIF), and it also gives partial eclipse info for Russia, Norway & Sweden, Portugal, Senegal, and down to Bolivia. ---
**Author:** ![TreacherousCretin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/treacherouscretin/32/476_2.png) [@TreacherousCretin](https://boards.straightdope.com/u/TreacherousCretin)\ **Post date:** [April 7, 2017, 4:24pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/127 "2017-04-07T16:24:35Z")
> [@Bullitt](#): > > I realize that while the imprecise map gives partial eclipse information for CONUS, it does not fully answer you. This NASA map does, [https://eclipse.gsfc.nasa.gov/SEplot/SEplot2001/SE2017Aug21T.GIF](https://eclipse.gsfc.nasa.gov/SEplot/SEplot2001/SE2017Aug21T.GIF), and it also gives partial eclipse info for Russia, Norway & Sweden, Portugal, Senegal, and down to Bolivia. “Imprecise” was good enough for me, or so I thought before I saw this. You are a gentleman as well as a scholar, and I thank you. ---
**Author:** ![Bullitt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bullitt/32/5725_2.png) [@Bullitt](https://boards.straightdope.com/u/Bullitt)\ **Post date:** [April 7, 2017, 4:28pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/128 "2017-04-07T16:28:54Z")
> [@TreacherousCretin](#): > > “Imprecise” was good enough for me, or so I thought before I saw this. You are a gentleman as well as a scholar, and I thank you. I’m glad it helped. ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [April 7, 2017, 11:27pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/129 "2017-04-07T23:27:48Z")
A little Google-fu showed me a website to a welding supply store not far from me, and I went there today and in the end purchased a 3x4" piece of welding glass at shade 12. None of the people working there had heard of the eclipse, so I would have been the first person to come there asking about this. I told them that I definitely won’t be the last. 🆒 😉 ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [April 7, 2017, 11:55pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/130 "2017-04-07T23:55:25Z")
I hate to tell you this, but #12 glass isn’t really good enough for solar viewing. You should get #14. Citations: [Perkins Observatory](http://perkins.owu.edu/solar_viewing_safety.htm) > [@](#): > > Be careful that you use the right kind of glass! Welder’s glass is numbered from 1 to 14 with 14 being the darkest. It is only number 14 glass that is dark enough for solar viewing! [NASA](https://eclipse.gsfc.nasa.gov/SEhelp/safety.html) > [@](#): > > One of the most widely available filters for safe solar viewing is a number 14 welder’s glass, available through welding supply outlets. [Sky and Telescope](http://www.skyandtelescope.com/observing/celestial-objects-to-watch/solar-filter-safety/) > [@](#): > > Welder’s glass of shades 12 through 14 are popular and safe solar filters, easily obtained at welding-supply outlets. Most observers prefer shades 13 or 14; the solar image through a number-12 filter is uncomfortably bright. ---
**Author:** ![Bullitt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bullitt/32/5725_2.png) [@Bullitt](https://boards.straightdope.com/u/Bullitt)\ **Post date:** [April 8, 2017, 2:59am UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/131 "2017-04-08T02:59:54Z")
Remember there’s a new ISO standard, dated from 2015. My cardboard viewers were about $1.50 each. They came in a sturdy cardboard tube and that’s what they’ll be transported in. They’ll stay in there until eclipse day. > [@Bullitt](#): > > I ordered here – [Contact eclipse2024.org - the Great North American Eclipse of April 8, 2024 | eclipse2024.org](http://www.eclipse2017.org/glasses_order.htm). 🆒 > > The safety standard is here: [ISO 12312-2:2015, Eye and face protection – Sunglasses and related eyewear – Part 2: Filters for direct observation of the sun](https://www.iso.org/standard/59289.html). [🆒](https://www.iso.org/standard/59289.html) I will take them out one bright sunny day, though, to look at the sun. 🆒 ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [April 8, 2017, 4:03am UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/132 "2017-04-08T04:03:51Z")
> [@markn\_1](#): > > I hate to tell you this, but #12 glass isn’t really good enough for solar viewing. You should get #14. > > Citations: > [Perkins Observatory](http://perkins.owu.edu/solar_viewing_safety.htm) > [NASA](https://eclipse.gsfc.nasa.gov/SEhelp/safety.html) > [Sky and Telescope](http://www.skyandtelescope.com/observing/celestial-objects-to-watch/solar-filter-safety/) #12 was the darkest they had, and I could barely see the very visible sun through it. #11? That was painful. It was in a mostly-white wrapper, and I was able to push some of the glass into a clear area of the envelope and test different strengths. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [April 8, 2017, 4:31pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/133 "2017-04-08T16:31:44Z")
That’s hard to understand. I wonder if it was mislabeled or something. I can easily see the sun, and sometimes see sunspots, through #14 glass. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [April 8, 2017, 4:40pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/134 "2017-04-08T16:40:50Z")
I have used the equivalent of #14 in all the eclipses I’ve photographed, and also [this composite](http://s174.photobucket.com/user/flamingriver/media/TOV001a_sRGB_x800.jpg.html?o=17) of the 2004 Transit of Venus. I wouldn’t use anything less. ---
**Author:** ![TreacherousCretin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/treacherouscretin/32/476_2.png) [@TreacherousCretin](https://boards.straightdope.com/u/TreacherousCretin)\ **Post date:** [April 8, 2017, 9:02pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/135 "2017-04-08T21:02:57Z")
> [@panache45](#): > > I have used the equivalent of #14 in all the eclipses I’ve photographed, and also [this composite](http://s174.photobucket.com/user/flamingriver/media/TOV001a_sRGB_x800.jpg.html?o=17) of the 2004 Transit of Venus. I wouldn’t use anything less. That is one hell of a nice photo. ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [April 8, 2017, 9:56pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/136 "2017-04-08T21:56:24Z")
> [@TreacherousCretin](#): > > That is one hell of a nice photo. I agree … it’s even in focus … ---
**Author:** ![Bullitt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bullitt/32/5725_2.png) [@Bullitt](https://boards.straightdope.com/u/Bullitt)\ **Post date:** [April 8, 2017, 11:58pm UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/137 "2017-04-08T23:58:48Z")
That _ **is** _ a very nice photo. ---
**Author:** ![Morgyn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/morgyn/32/3041_2.png) [@Morgyn](https://boards.straightdope.com/u/Morgyn)\ **Post date:** [April 9, 2017, 3:08am UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/138 "2017-04-09T03:08:02Z")
I’m trying to find #14 shades that will fit over prescription lenses. Almost all the eclipse glasses I’m seeing don’t say whether they’ll fit over regular glasses, and they all seem to be #5. I’m in luck on location. One of my cousins lives just south of St. Louis; we’ve never met but have gotten to know each other on FB. Road trip! ---
**Author:** ![Bullitt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bullitt/32/5725_2.png) [@Bullitt](https://boards.straightdope.com/u/Bullitt)\ **Post date:** [April 9, 2017, 5:30am UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/139 "2017-04-09T05:30:00Z")
> [@HeyHomie](#): > > I live /just/ outside the path of totality - as in, a few thousand meters. A 40-minute drive north (to Sullivan, Missouri) and I’d be right in the middle of the path. But instead, Mrs. Homie and I are driving about two hours east, to Saint Genevieve, Missouri, to see it. St. Gen is a much prettier town, so we’re going to see the tourist attractions, get some lunch, make a day of it. > > I live in fear of it being a cloudy/rainy day that day. > [@Morgyn](#): > > I’m trying to find #14 shades that will fit over prescription lenses. Almost all the eclipse glasses I’m seeing don’t say whether they’ll fit over regular glasses, and they all seem to be #5. > > I’m in luck on location. One of my cousins lives just south of St. Louis; we’ve never met but have gotten to know each other on FB. Road trip! Ste. Gen – Sounds like you guys may be close to each other there. ---
**Author:** ![gkster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gkster/32/14107_2.png) [@gkster](https://boards.straightdope.com/u/gkster)\ **Post date:** [April 9, 2017, 8:47am UTC](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593/140 "2017-04-09T08:47:36Z")
So, in terms of weather, would Illinois be a safer bet than South Carolina? We live in the NYC area and have time for a road trip; we could go to friends in Hilton Head SC or relatives in Zionsville IN, both of whom have asked us more than once to come and visit them. It looks like totality would be a 3+ hours drive from Zionsville and a 1-2 hour drive from Hilton Head. [Previous page](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593.md?page=6) [Next page](https://boards.straightdope.com/t/solar-eclipses-partial-vs-totality/782593.md?page=8)