1. Don't plan to drive anywhere on eclipse day (90% of the US lives within an 8hr drive of totality, so traffic will be horrible)
2. A 600-800mm lens is optimal for photography. Anything short of 200mm is useless.
3. Don't make any solid plans until 3-4 days before. Most places only have about 40% chance of it being clear.
4. If you're photographing the partial phases. Stop and check everything (batteries, memory card, focus, etc) about 5 min before totality.
5. If you have any technological issues during totality, just sit back and enjoy watching it.
6. On eclipse day, if you're in a place that has 2 min or more of totality, just stay there. There's not a lot to be gained by risking moving.
7. All across the US, the sun will be high in the sky, good horizons aren't necessary.
90% of the US lives within an 8hr drive of totality, so traffic will be horrible
August 21st is a Monday afternoon, so how many employed Americans are going to ask for the day off, to drive 8 hours, with a 200mm telephoto lens or telescope?
If totality is the size of several counties, and lasts even ten minutes, how many people will be on the road within an hour of the event? Lunchtime (or even all day long) traffic is probably nothing even terrible in 40 out of 50 states. In totality states, traffic won't even compare to a sporting event.
Hotels across Oregon are already booked solid. Court Priday, manager of the Inn at Cross Keys Station in Madras, said rooms have been gone for a long, long time. "We've been getting phone calls like crazy," he said. "We've been sold out for about three years."
But in general, unless you happen to glance at the sun in your field of view during the eclipse, it's all the darkness of passing clouds for most of the country.
Are traffic accidents statistically affected by proximity to a total eclipse of the sun?
I watched a total eclipse in England in 1999 parked up on the side of the road with other cars doing likewise as far as the eye could see in both directions. Traffic was at a standstill all morning.
Get to where you want to be the day before, and stay there.
Really good points that you made, but I personally think it's good to find a high location with a view so you can take in more than just the sun/moon.
Since the dawn of photo sites on the web, I've completely stopped taking photos of anything except family and friends. What's the point when a thousand photos exist of everything, from every conceivable angle, within 5 seconds of googling.
Even if you manage to get an incredibly cool picture, then what? Nobody pays for photos anymore. Your closest friends will give you a "like" and move on to a million other cool photos. Chances are that even you will never look at your photos again having amassed tens of thousands of them.
It's going to get much worse within a few years. With continuous surveillance cameras everywhere and "life recorders" capturing in high resolution and 360 degrees there won't be an event witnessed by human eyes that hasn't already been photographed or videoed.
Photography as a creative endeavor is dead but people don't know it yet.
Speaking of driving, anyone from the Seattle area have any thoughts on the best approach?
The first one that comes to mind is to take 5 down to the path of totality.
The second thing that comes to mind is heading east toward Spokane, and turn south at Yakima and head on down 84 to somewhere in totality.
I've driven the 5 route a few times going between Seattle and California, so I know the roads are reasonable. The big unknown will be traffic. It will have a lot of people from Washington heading down plus the Portland crowd.
I've never headed east from Seattle past, I think, North Bend, so nearly everything on the second route is completely unknown to me.
The Spokane option might work but the unknown there is that most of the roads in Oregon will be one lane each direction with hundreds of thousands of visitors expected in that area.
There's more to eclipse than looking at the sun. Horizon is also very important, especially the unobtrusive western horizon, where the shadow is coming from, and where you can see dancing light rays from beyond the shadow.
Photography is really not recommended, unless for science, since you have really two minutes of the greatest spectacle of nature, and photography doesn't really do justice to its grandeur.
Drive, and try to get there!
Only if your goal is a closeup shot. I'd be much more interested in a shot with significant context. How easy that is to pull off I don't know, but I'd love to a nature landscape shot @28-35mm (FF) with the eclipse in the sky instead of the sun or moon.
But if you want any of the partial phases, you need a solar filter (not just ND filters), and that thing basically blacks out anything that's not the sun.
It seems like there's a lot more hype around this one; I'm not sure why. Maybe 'total' vs 'annular'? Personally, I think they're both pretty spectacular, and annular eclipses have the added benefit of having the awesome ring-of-fire effect.
> Don't make any solid plans until 3-4 days before. Most places only have about 40% chance of it being clear.
If you haven't made plans already, you are probably driving.
Best I could do was get a room in portland the night before. Gonna have to get up stupid early and try to make it. 3-4 days before is gonna be tough.
(For others:) A diagram of the umbra makes this clear:
If you draw a few triangles, you can get an analytic expression.
The first is the eccentricity of the lunar orbit - 0.0549 which means that depending on where in the lunar orbit the eclipse occurs, the moon is closer or further away meaning the apparent size ratio between the Sun and Moon varies. In fact - it's even possible to have an eclipse where the Sun's limb is visible around the edge of the Moon at totality - this is called an annular eclipse. 
The second factor is that the Moon is lumpy! The depressions caused by craters and valleys means that totality, as defined as when the Moon completely occults the Sun's disc, varies according to where in the path of totality you are. Parallax effects move the Sun with respect to the observed position of the Moon, so the Sun will peek through the valleys/craters earlier or later depending on your latitude. This lumpiness actually creates one of the most spectacular features of a total solar eclipse, the "diamond ring" effect - I had the rare privilege of seeing this in the 1999 eclipse that crossed south-west England and northern France - a mere teenager but the image is burned into my brain. 
Other minor factors come into play which add to why the shape of the polygon changes across the track - the Earth is a spheroid, not a flat plane so the ratio of Sun:Moon coverage varies along the track; also the Moon is still gently turning as it orbits in a manner called libration - while tidally locked to face the Earth, the Moon still rotates marginally faster or slower along its orbit. 
The effects of the compensation for totality variation are shown in the second half of the video past ~1:20.
As a bonus a friend of mine's family winery has booked Ozzy to "bark at the moon" during the eclipse: http://loudwire.com/ozzy-osbourne-headlining-moonstock-solar...
I'm staying in St Louis the night before and then picking a direction to drive based on weather. I don't think it's worth all the hassle to get to southern Illinois just to get 3 more seconds of totality.
This map will show you how much totality you can experience, unlike the NASA charts.
I fully anticipate traffic to be screwed up for hours afterward.
I have to say, though, I'll probably leave earlier that morning than I'd originally planned, because of the comments in this thread.
If you have seen a total eclipse before, then you don't need any convincing.
I was planning to have my 5 year old son see it. But now I wonder whether it will have any traumatic effect on him.
In any case, I saw my first near-total solar eclipse at about your son's age. I don't recall as it did me any harm - indeed, I thought it was brilliant. The only real cause for trepidation would be looking at it with bare eyes, but there exist any number of expedients there.
Many total solar eclipses happen over the middle of the ocean, or at the poles, or in a location that is not as easily accessible.
The next eclipse (after this one) to pass through the United States is in 2024.
You can photograph the eclipse, but you will have a much grander experience if you don't try. Photography is just a distraction from the awesome spectacle of the eclipse, including the phenomena that happen on the ground.
There will be plenty of other people taking great photos, so enjoy those after the eclipse. A total eclipse, viewed directly with your own eyes, is truly an experience of a lifetime. No photograph comes close.
Contrary to one or two other comments, eye protection is not necessary during totality and will prevent you from seeing the full beauty of the corona. It is perfectly safe to view the total eclipse with the naked eye, or even with binoculars. Only the partial phases need eye protection (and they definitely do).   
In fact, on the hillside we ended up at, something interesting happened. Most of the people wore dark sunglasses and faced away from the sun during the first partial phase, in order to get their eyes a bit acclimated to the dark. The partial eclipse isn't very interesting compared to totality, and the fun stuff at that point is happening on the ground: there are ripples of light dancing on the ground like you see on the bottom of a shallow stream. And you may get to see the shadow rushing toward you at 10,000 miles an hour!
The moment it reached totality, there were shouts of "it's total!" up and down the hill. Everyone took off their sunglasses and looked directly at the total eclipse. Many of us brought binoculars and viewed the corona with them.
The danger is that it is tempting to keep looking at the end of totality, when the string of beads starts to appear at the edge of the moon (where the sun is starting to peek through the moon's valleys), and finally the "diamond ring" where a larger part of the sun appears through the deepest valley. If you bring proper eye protection, switch to it the moment the string of beads appear, and definitely before the diamond ring appears! I recommend doing this after totality and not before, so you don't interfere with your eyes' dark adaptation before totality.
That's a quote from one of the links. Most people will not be in totality. Most people will only be seeing a partial eclipse. The shaded in line from this  image is where totality will happen.
Most people watching the eclipse will need some form of eye wear.
 - https://nasaviz.gsfc.nasa.gov/vis/a010000/a012400/a012458/us...
But thank you for making it more clear that viewing any other kind of eclipse - partial or annular - requires proper eye protection!
"A total eclipse, viewed directly with your own eyes, is truly an experience of a lifetime. No photograph comes close."
This is _so_ true.
> HOW TO WATCH THE ECLIPSE (AND SHADOW SNAKES) - Smarter Every Day 171
It is an amazing spectacle (provided there are no clouds), and certainly worth some travelling to see it.
Solar filters: https://www.bhphotovideo.com/c/buy/solar-photography-filters...
I'll also have a timelapse camera set up on a wider angle (incorporating my yard, some trees, the sky, etc.) using pi-timelapse
I have to drive about 15 miles south from my house to get deep into the totality, and I know all the back roads, and I still expect epic gridlock.
Since I'm about 1.5 hours from the path of totality in Georgia, my current plan is to drive out at like 3AM (before the roads have a chance to get packed) and just stay in the area.
If it looks like the weather isn't going to cooperate, I'm going to leave a day earlier. Get a hotel outside of the path of totality, and do the same thing I was planning to do at home (leave at 3AM to drive into it).
On the other hand, the totality will pass in the very early afternoon, so I can probably just head back once it's over.
A train is going to take me 16 hours, minimum - and a car will take 12. I might just go ahead and book a flight, but then I still need a car.
There were some big news stories here in Oregon about this. People made reservations literally a year in advance, only to have the hotels cancel them once they figured out why people were booking!
The only good news is some hotels may have done people a favor. Those were on the Oregon coast, in the Lincoln City and Newport areas, where, even in the middle of August, there's a good chance of overcast skies (marine air).
And I don't trust people not to cancel early bookings once they realize what kind of prices they can get.
Yes the hotel prices are very high, but I hadn't seen any that high.
Not expecting it to be anything flash, but there's stuff out there. Don't be put off!
I waited too long to plan and we're flying (ourselves) up to Idaho Falls and paying like $700/night. Selection was really bad and virtually every other town I tried had zero availability at any price!
...would you have any advice on where you think we might want to go (assuming we're not fighting clouds)?
We could only get our campground on the night of the 20th, so don't have time to do reconnaissance as we would have wished; the main thing is just to make sure we get somewhere with a view of some kind.
(I lived in Utah as a kid and came up through the area many times but can't correlate my ancient memories with places...)
Wyoming is the way to go, or western Nebraska. Don't expect to get hotels, but camping on a rancher's land is easy, and the arid climate in the summer minimizes chances of cloud cover.
Perfect example of the Cascades blocking the crap.
That said, it looks like things are going to be a complete and total mess here in central Oregon with all the people converging on this area.
I'll be in eastern Nebraska (Omaha) and will drive south on I-80 towards the eclipse path and hopefully pull off to the side and park somewhere.
What's hard to plan for is whether too many other Nebraskans will have the exact same idea which means I have to camp out a ridiculous 12 hours before the event to secure a spot -- or give up entirely.
PS: Sure, the closer to the center the longer the total eclipse lasts. But, you still end up seeing the same thing.
True but I was trying to minimize the distance from Omaha airport since I have to catch a flight 5 hours later. It will be interesting to see how many of the ~500,000 Omaha residents will be on that stretch of I-80!
How much better is a 100% eclipse vs. a 90% eclipse that we'll get here?
Is it worth the trip to Wyoming? I think so, but not positive.
I plan to find a spot 6 hours early but my worst fear is that everybody else camped out 12+ hours before I did. Or there is unforseen traffic gridlock towards the path of totality.
>everybody else camped out 12+ hours before I did
Basically every spot is a good spot as long as you can get to it. Gridlock starting the day before is the only problem I can foresee that would keep me from actually getting there.
I'll probably pack the bikes in the insane case that I have to leave my car on the side of the road 20 miles outside of the path of totality or something. But the only way I see that happening is if it turns into something like a hurricane evacuation.
I thought the last full eclipse to cross the USA was in the late 70's??? Pretty sure it hasn't been since 1918.
Yep, I was right:
Right, but that 1979 one didn't reach the major metro areas across the entire swath of USA-48. That's what people mean by comparing it to 1918 in terms of widespread national interest.
The eclipses of 1918, 2017, and 2024 attract extra attention because of the paths crossing numerous population centers.
Probably gonna have a hard time.
Will the April 2024 one be as good as this one?
I suppose one drawback of that one is that april is probably(?) much larger risk of clouds in a lot of the US, than august?
I'd like to ask anyone who lives on the midwest or east coast to consider helping these projects:
1. EclipseMob: http://hamsci.org/node/148
This project will ship you a set of ICs and a breadboard that will make up a VLF receiver. No soldering is required. It's a great kit to put together with children.
After you build up the kit you plug it into your phone's microphone jack and run an app that agregates radio signal information (I/Q data I think) to the EclipseMob organizers. After the eclipse is over you'll still be in possession of a fully capable VLF receiver kit. You can use it to listen to VLF signals that are interesting. This may include human generated traffic or whistlers.
2. Total Eclipse SEQP: http://hamsci.org/seqp
If you have an amateur radio license and want to help participate in a contest you can hop on the air and operate during the eclipse. The more people on the air the better dataset we have.
3. Setup a Reverse Beacon Network receiver.
The main dataset we use is the Reverse Beacon Network. It's a set of automated receivers that listen to short-wave Morse code and RTTY communications. If you have a few bucks burning a hole in your pocket and want to set up a we have a page that talks about how to do this: http://hamsci.org/cw-reverse-beacon-network-how-guide
Using these data sources we would like to generate a very high resolution picture of the effects of a solar eclipse. As it turns out we don't exactly have the best understanding of what goes on during an eclipse.
We have a few other projects in the works that I'm not very familiar with. One idea is recording I/Q data from JT65 bands and building a data set via Zenodo so that everyone who contributes to the data set gets their name as a reference on papers that use it.
If you're interested and want to hear more about this you can reply to this post or send me an email to my "work" email. My email username is jk369 and my university's mail address is njit.edu.
You shouldn't count on this, try positioning for good weather in advance regardless, but just keep it in mind so you don't crash your car heading for better weather if things look poor.
I've been in Atlanta too long.
We were going to make a weekend trip out of this. But we realized the chances of bad weather are pretty high at our planned viewing site in Western North Carolina and that it would be better to stay in Atlanta closer to an Interstate Highway so we can quickly drive to an alternate site.
The last US West Coast to US East Coast eclipse was 1918.
The last time the totality was entirely within the current US borders and never over land elsewhere was 1257.
The interactive map: https://eclipse2017.nasa.gov/sites/default/files/interactive...
will tell you exactly when and for how long you'll get totality anywhere along the route.
I have several hundred miles if I wanted to go to the totality zone. But I'm still curious what it will look like in the difference of 100% vs 82% at my home.
There was a total eclipse in Britain when I was a child , and everyone bought special protective glasses to wear.
Mine were like the paper red-green "3d" glasses you used to get, but with a black film that was close to opaque. They worked fine.
 http://xjubier.free.fr/en/site_pages/solar_eclipses/TSE_1999... ("Britain" is exaggerating, but we were in Cornwall on holiday.)
But once the totality starts in your location, you can pop off the filters/shades and look with the naked eye. Just be sure to put them back on once totality is just about over!
PNG is a reasonable alternative, usually, but TIFF is entrenched. TIFF had legal issues in the past with respect to the LZW compression, which is a shame. PNG might never have been needed if TIFF had been free of patent encumbrances.
The format is very extensible. It was originally specified to have 5 ways to encode data: uncompressed, LZW, fax, RLE, and JPEG. The use of proprietary encodings is normal however, along with several non-proprietary encodings. Data can be lossless or not. Data can be bitmap or vector. There are even two different ways to store JPEG data, with many tools supporting only the original style and many other tools only supporting the newer style.
Now consider trying to view a TIFF that you have received. You have a several TIFF-capable image viewers. No two of them handle the same set of encodings. The most recently installed viewer is associated with the file extension, and as a normal user you are thus unable to use the other viewers. If you install another TIFF-capable viewer, you gain the ability to view some TIFF images while losing the ability to view some other images.
PNG just works. JFIF and EXIF JPEG do too, because nobody creates 12-bit or arithmetic-encoded files. GIF just works.
Then, you project the light from the sun onto the earth, with the moon in-between. This creates the 2D shape on the earth's surface corresponding to the shadow.
I've set up something very similar to this in Blender, although its floating point precision was too low, so I had to fudge things a bit.
I would be curious to hear what tool they actually use, their pipeline, etc.