2023 Annular Solar Eclipse Trip - October 13-15, 2023

[DaveInDenver]

Good post Allen!

Another option is to double up to get to 12, which I've read is considered the absolute minimum to look at the Sun, although NASA does recommend 14 and even then you should limit the time.

My reasoning during the total was that since mine is auto darkening at the lower end of welding plus with the goggles value of 6. I figured the hood would sense when the Sun had been obscured enough to risk looking without as much darkening and I wouldn't go from full dark down to none. There was a period when the Baily's Beads would be visible but before totality that I wanted to try and see.

Baily's beads - Wikipedia

en.wikipedia.org

NASA - Eye Safety During Solar Eclipses

This is NASA's official moon phases page.

eclipse.gsfc.nasa.gov

NASA - Eye Safety During Solar Eclipses

This is NASA's official moon phases page.

eclipse.gsfc.nasa.gov

 

[allen.wrench]

I wondered if doubling up on shades would add them together. I have an auto darkening helmet that goes up to shade 13 and a shade 5 pair of oxy safety glasses. In addition to this shade 14 (now) set of goggles.

Is it like a shade 5 lens behind a shade 6 lens will be as dark as a shade 11 lens? Speaking hypothetically to understand how that works.

At the end of this Sept I'm planning on getting LASIK. Maybe they'll install laser and/or x-ray vision while they're there. But so I want to play it safe right after.

Allen

 

[DaveInDenver]

Welding shades are given by a DIN standard scale and it's a measure how much light is allowed through. It's not a linear scale, found using these equations.

OD = -log T
SN = 1 + (7/3) OD

optical density is OD
fractional transmission is T (given as luminous transmittance in the chart)
shade number is SN

A shade with 99.9% blocking (e.g. 0.1% transmittance) would be a T = 100 - 0.999 = 0.001, which results in an OD = 3. Thus SN = 1 + (7/3) * 3 = 8.

Since it's logarithmic you can't just sum the numbers directly but you can add the logs, e.g. log X + log Y = log X * Y, by the product rule.

You can stack two lower filters to get more blocking but it wouldn't be 2 + 2 = 4 but rather 2 + 2 = 3. As you go up in shade numbers the effect would be 7 + 7 = 13 or perhaps 5 + 10 = 14.

I don't remember what I had my welding helmet set to exactly. My brazing goggles are 6 and I'd guess I used something like 10 to 12. So assuming it was 10 the value would be 6 + 10 = 15. I remember it being comfortable anyway.

BTW, it's important to also mention that this is only visible light. Looking at the Sun involves tremendous infrared and ultraviolet light. This is really the damaging part. Not all welding filters are necessarily good IR and UV, too. Those are present in weld arcs but the dark filter itself might not provide the filtering. It might be a separate piece.

Auto darkening filters may be a better choice for this because they will continue to work on UV and IR regardless if they are optically dark or not. That's a required safety in the event your battery dies (this is one reason to buy auto darkening helmets that are DIN/ISO/AWS/OSHA approved). So if you do inadvertently flash yourself you may get spots for a while but won't cook your eyes permanently. Also without good UV/IR filtering the slight darkening time would be cumulatively damaging.

 

[allen.wrench]

That's making a lot of sense. Thanks Dave!

Allen

 

[DaveInDenver]

That's making a lot of sense.

Well the makes it so to 3 so far then. Shill for big math here!

 

[nakman]

Well the makes it so to 3 so far then. Shill for big math here!

So Dave, what do you think about something like this.

Amazon.com: Soluna Solar Eclipse Glasses - CE and ISO Certified Safe Shades for Direct Sun Viewing - Made in the USA (5 Pack) : Tools & Home Improvement

Shop Amazon for Soluna Solar Eclipse Glasses - CE and ISO Certified Safe Shades for Direct Sun Viewing - Made in the USA (5 Pack) and find millions of items, delivered faster than ever.

www.amazon.com

CE and ISO Certified for direct sun viewing!​

 

[DaveInDenver]

So Dave, what do you think about something like this.

Amazon.com: Soluna Solar Eclipse Glasses - CE and ISO Certified Safe Shades for Direct Sun Viewing - Made in the USA (5 Pack) : Tools & Home Improvement

Shop Amazon for Soluna Solar Eclipse Glasses - CE and ISO Certified Safe Shades for Direct Sun Viewing - Made in the USA (5 Pack) and find millions of items, delivered faster than ever.

www.amazon.com

CE and ISO Certified for direct sun viewing!​

Seem to match what those NASA pages say for annular or just before and after totality - #5 shades, 100% UV and IR.

Eye Safety During a Total Solar Eclipse

NASA.gov brings you the latest images, videos and news from America's space agency. Get the latest updates on NASA missions, watch NASA TV live, and learn about our quest to reveal the unknown and benefit all humankind.

www.nasa.gov

 

[Inukshuk]

Y'all have too much brains and time. I bought 20 paper eclipse certified glasses for $25 www.eclipse2024.org

 

[Inukshuk]

I still plan to camp around or North of the center of Annularity Friday night and find a good view spot for Saturday. If this interests you, post up.
I already have to be in NM for 4x4 stuff starting 10/15 which is why I chose this location. There are many options. I won't be able to leave the Denver area till Friday AM and most likely after the Eclipse Saturday I will be off to my other stuff, but I might camp again Saturday. Not sure.

 

[DouglasVB]

Since we're out in Cali, I think we're going to go up toward Lakeview, OR or Winnemucca, NV to watch. Hotels are a bit scarce but still possible to find at not insane prices.

The big one next year... that's the one we need to plan well in advance.

 

[Oh_shift]

Can’t wait to see everyone’s photos from today!

 

[Crash]

It’s pretty cool!

 

[bh4rnnr]

Looked outside my window this morning only to see a guy in the parking lot across the street looking up at the sky through a shoe box. A bit odd I thought, but again, I do live downtown. Then noticed how dark everything was. Hope you guys got to enjoy it.

 

[On the RX]

 

[Inukshuk]

Worth the trip.
TX or MX 2024!

 

[allen.wrench]

 

[MonPetiteShoe]

Big Eclipse Mood.

 

[DaveInDenver]

Thought we were clever in where we decided to go only to find apparently a big group of hippies and hipsters from California had the same idea. So more people buzzing around than I'd thought (hoped). About 24 miles north of umbral center so got an almost perfectly centered ring.



But we found our own private Utah and it was quiet enough for a couple of days.



Pictures weren't working so we just experienced it not looking through a viewfinder.

 

[Seldom Seen]

Ended up about an hour south of Farmington, at he trailhead for the Bisti Badlands Wilderness, less than a mile from the center line of annularity.

 

[fyffer]

Ended up about an hour south of Farmington, at he trailhead for the Bisti Badlands Wilderness, less than a mile from the center line of annularity.

Love, Bisti De Na Zin/ Badlands. Amazing Hodoos and great hiking in Cool weather.