## Longest lines of sight photographed.......

Post general questions and discuss issues related to climbing.

Day Hiker

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RickandRhonda wrote:Given perfect conditions, and taking earth curvature into consideration, your horizon would be approximately 257 miles away on Rainier. Theoretically, your horizon on Denali would be 304 miles away. This assumes perfect conditions, and is the mathematical maximum.

Source: http://newton.ex.ac.uk/research/qsystems/people/sque/physics/horizon/

Very interesting project. I'll be interested to see just how far from Rainier I can get and still see it.

Please note: the formula I mention only calculates the theoretical distance between the height of an object and the horizon. It does not calculate the theoretical distance between two peaks. (And is thus, slightly off topic.)

Using the link you provided, which appears to be correct, using the formula d^2 = 2rh + h^2, the theoretical horizons for Rainier and Denali are not what you wrote. Note the form's elevation field requires meters. So Rainier at 4392 meters has a sea-level horizon distance of 236.7 km (147.1 mi). The calculation for Denali at 6194 m gives 281.2 km (174.7 mi).

I could not figure out what numbers you entered to get 257 and 304 miles.

Day Hiker

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Here is a photo of the lofty Mount Sunflower from 438 miles away (on the extreme left edge of the image):

(From Landsat satellite, orbit height 438 miles.)

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I always thought Mt Kenya to Kili was the furtherest visible distance between two pints?

nartreb

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Iron Hiker mentioned Camel's Hump back on the first page of this thread. Never having been to the Catskills, I can't verify that Camel's Hump is visible from there, but here's a photo of the Hump from Mt Carrigain, fairly southeasterly in the Whites. Length of view here = about 100km. (I couldn't figure out how to directly query HeyWhatsThat.com about the view from Carrigain to Camel's Hump,, but it does say Carrigain's view includes some farther peaks, such as Killington at 123km.)

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Day Hiker wrote:
RickandRhonda wrote:Given perfect conditions, and taking earth curvature into consideration, your horizon would be approximately 257 miles away on Rainier. Theoretically, your horizon on Denali would be 304 miles away. This assumes perfect conditions, and is the mathematical maximum.

Source: http://newton.ex.ac.uk/research/qsystems/people/sque/physics/horizon/

Very interesting project. I'll be interested to see just how far from Rainier I can get and still see it.

Please note: the formula I mention only calculates the theoretical distance between the height of an object and the horizon. It does not calculate the theoretical distance between two peaks. (And is thus, slightly off topic.)

Using the link you provided, which appears to be correct, using the formula d^2 = 2rh + h^2, the theoretical horizons for Rainier and Denali are not what you wrote. Note the form's elevation field requires meters. So Rainier at 4392 meters has a sea-level horizon distance of 236.7 km (147.1 mi). The calculation for Denali at 6194 m gives 281.2 km (174.7 mi).

I could not figure out what numbers you entered to get 257 and 304 miles.

Yeah, you see, I used the calculator on the page I linked to. I entered in the elevation of Rainier, and then multiplied the results by .6 to convert from metric to standard. I'll freely admit that I didn't do the work, I just used the calculator. Of course, if I had pulled my head out, I'd have recognized that I entered 14,410 meters, not feet. Doh. Thanks for pointing out my error. I'll fix it.

Iron Hiker

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About the view from the Grand to the Uintas, Scott -

The Heywhatsthat pano from the Grand at its exact elev of 13,770 feet shows not one speck of red on the Uintas in the areas that you mentioned. The line of sight does pass between some of the bigger ridges in the Wyoming Range, but has to pass over at least one 10,000 foot area before entering the flatter regions to the south. I have heard of atmospheric refraction (and www.viewfinderpanoramas.org has some fantastic examples of that), but I'm not sure if that would be enough to make the very tips of the Teton peaks poke above the horizon looking north from the Uintas....... I think a nice zoom in pano shot of the Winds would be more fantastic and realistic .

As for the Camel's Hump/Black Dome view (and to Windham High Peak as well), I actually mentioned that to Jonathan de Ferranti (Viewfinder) in the only email conversation I had with him, and he confirmed that it was indeed possible. It beats the Washington/Marcy view by about 20 miles (which, by the way, is photographed on this excellent AccuWeather post by a Mount Washington observer):

http://www.accuweather.com/mt-news-blog ... a_view.asp. (hmm, doesn't seem to go all the way, just click on the link, then go to Monthly Archives>October 2008> What a View!)

Camel's Hump actually seems to be the penultimate summit in the entire East for long-range views, being located at a perfect spot at the edge of the long, low, linear Hudson/Champlain valley so that not only can you see beyond the Adirondacks to the Catskills, but also ANOTHER (almost) 150-mile view to just east of Mont Tremblant in Quebec. Probably only the Smokies can come close to that one.

For sentimental reasons, I've always been amazed at the view from my local mountain that I grew up on, Sam's Point in the Hudson Valley of NY. It is only 2,289 feet high but has an incredible line of sight to the north - 120 miles to Mount Equinox in VT. I've never personally observed that view but have read accounts of a few people who did, and I've seen 90 miles to Mount Greylock in MA a few times. For the West, that's easy.......but don't despise us "lowlanders" who still have the Adirondacks, Katahdin, and many other rugged little hills to play on.

I just moved to the San Diego area by the way, so I'm now thinking "big".....

brendon

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Cache Peak also has possible visibility from Swasey in the west Utah desert, 194 miles. There is absolutely nothing between them. That's as far south as Delta, UT.

I'm just looking at local interest, but I'm betting there are lots of possible 200 mile views.

BTW, if you open your view in google earth, the cloak outline shows you harder to find far points.

Day Hiker

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brendon wrote:
Scott wrote:
The Winds to the Uintahs could get up to some high numbers.

Or even more so, the Uintas to Tetons. You can see one from the other on very clear days.

I would still guess that the Cascade Volcanoes probably take the cake in the lower 48.

Denali, Hunter and Foraker can all be seen from Mount Sanford. Foraker is 240 miles away. I wonder if Denali can also be seen from even more distant peaks in the Wrangells.

Maybe, but the entire bulk of the Wyo. Range is in the way.

This map- http://www.heywhatsthat.com/?view=BS5JALP9 -doesn't show much in that direction, a couple of spots in the desert near Big Piney. The furthest line of site that I could find for the Grand is Hyndman Peak at 166 miles.

Another interesting note, the furthest point on the valley floor where there might be a possibility of seeing the Tetons is 134 miles away. Pillar Butte in the Great Rift. I think that's within my hometown school district (and ward) boundaries.

Also, the Diamond Peak -> Teton Range view might be one of the easiest 120 mile views to find, can't miss the Tetons.

The image I generated with my program shows the view from Grand Teton to Hyndman Peak is blocked by the Lost River Range, south of King Mountain, right around here:
http://www.mytopo.com/maps.cfm?mtlat=43.75685&mtlon=113.25851
The distance to this point from The Grand is about 122.6 miles. Hyndman's distance is about 166.1 miles.

In that direction, the farthest point I found is one at a distance of 155.2 miles, here:
http://www.mytopo.com/maps.cfm?mtlat=43.65366&mtlon=-113.90727
I did not check the entire 360-degree view from Grand Teton's summit, only the direction toward Hyndman, specifically a 12-degree arc between bearings 265.3 and 277.3.

Next, I can check views to Wyoming from the Uintas (Kings Peak?). Viewing peaks in the Wind River Range looks more likely than the Tetons, but the Wind Rivers' distance from Kings would not be record-setting unless I can get something on the north end.

I am not familiar with the geography of the Uintas. I have never been there; I have only seen them from I-80 in Wyoming (which was really cool and beautiful!). And I only know that they are the 48's only major east-west mountain range, and Kings Peak is the highpoint and state highpoint. But I don't know details. So I need to know if Kings Peak a good viewpoint to use. Or are there other possibilities that should be checked?

brendon

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Thanks! Sorry I forgot to get back to your PM. Does your program account for curvature of the earth as well?

Oh, and is it downloadable and easy to learn?

Day Hiker

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brendon wrote:Thanks! Sorry I forgot to get back to your PM. Does your program account for curvature of the earth as well?

Oh, and is it downloadable and easy to learn?

For the first question, yes, for sure. Using a flat Earth would be quite inaccurate for anything more than several miles away. Here is more from another thread:

Day Hiker wrote:
David Senesac wrote:Day Hiker, quite like your simulation work. Does that work take into account earth curvature?

Yes, but a spherical Earth, not ellipsoid. Each data point is given an XYZ position in a 3-D Cartesian coordinate system, based on its latitude, longitude, and elevation:
X = (R+elev)*cos(lat)*cos(lon),
Y = (R+elev)*cos(lat)*sin(lon), and
Z = (R+elev)*sin(lat), where R is the Earth's radius. From this, the shading for the topographical surface is calculated.

Below is a simulated view of the Southwest, looking north from a point above southern Arizona (lat/lon: 32, -112). Some key features are indicated.

The viewpoint elevation is 500,000 feet (94.7 mi) above sea level, a point high enough for the Earth's curvature to be apparent. A sea-level horizon is about 12.4 degrees away from a viewer at 500,000 feet. The data used for this image extend to 45 degrees north latitude, which is well beyond the horizon formed by the Earth's curvature.

The horizontal angle of view is exactly 90 degrees; vertical AoV is about 67.4 degrees.

Obviously, since the colors are based on elevation only, the program's output does not show the true visual appearance of the Earth. But it makes the topography obvious.

An image that I would find useful is larger than this, but I have to size these appropriately for the Internet.

Regarding my program being available, it would be great to sell the thing to make a little money, especially now since I have been laid off from my EE job after seven years there. I don't want to be rich, just finish paying off the house, have a life here in Henderson, and take inexpensive hiking and climbing trips with family and friends.

I wrote the image-generating code myself with no outside help. I know all the math and programming required for that. And I could do some more work to make it easier to use for someone who buys it. But I don't know what I would need to do to be able to restrict the software to one user.

I spent over a thousand hours of personal time on this code in the last seven years or so. If I distribute it, I need it to be copyright protected where someone cannot just copy it for his ten buddies, and so on and so on.

So I am open to advice on how to protect it and market it. Meanwhile, I don't mind generating images and analyzing results like I did here. The topic of line-of-sight is of particular interest to me. I love mountains and views from them.

dirth

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One of the coolest views I have seen is from Marys peak in Oregon. It's a pretty small mountain, around 4000 feet. But it has great lines of sight east to the cascades and north towards St. Helens, Adams, and Rainier. I camped up there one night this winter and there was a solid fog ceiling around 2000 feet and above that is was incredibly clear. I thought I could see Rainier and I just checked "Hey, what's that?" and I think I was right. That's 184 miles, which is pretty substantial, especially for a mountain that is only ~4000 feet.

Hey what's that? doesn't seem to handle the ocean very well. It kind of craps out once it gets a little bit away from land. I tried to check Mauna Kea but the picture was pretty incomplete.

dirth

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Also, in response to the OP. Indian Mountain from Denali measures in as 222 miles (one mile over what he suspected to be the longest). There may be something longer, but I didn't have the patience to look anymore.

Edit: Also found Pinnell Peak from Denali at 238 miles (@ bearing 21°), but the site seems to be glitching out pretty hard right now and this may just be a symptom of that.

Iron Hiker

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Day Hiker, thanks for telling us more about your program. That's a pretty neat tool. Yes, I was suspicious of Hyndman because sometimes heywhatsthat has a few small glitches with its visibility cloak that make it seem like you can see ridiculously far (kinda like a little "spike" of red) or not at all. These glitches usually happen at 90 degree intervals (like straight east or west) and are mercifully narrow. It shows up well on the Grand Teton viewshed pano. Usually I can tell these glitches out when I see them.....so I don't think that's too big of a deal for heywhatsthat. At least it seems possible to see Smiley Mountain, that is consolation enough.......

Heywhatsthat is not perfect, obviously. I know about the ocean being messed up.....but usually when land is in the picture (such as other islands), the visibility cloak tends to compensate for that. Also please note that the Alaskan and non-US imagery is less reliable, so I wouldn't take as much stock in panos from these locations. The Denali pano, for example, doesn't even show up the Wrangells, which we do know to be visible from the viewfinder site and the recordholding 227-mile photo located on it. Hopefully they'll clear up these glitches and perhaps Viewfinder's data could help them on it too.......

As for the previous post, I was talking about the farthest PHOTOGRAPHED line of sight as being 227 miles from Denali. Besides what I mentioned on the previous paragraph, the viewfinder site's pano from Denali shows plenty of farther locations visible, like Mount Blackburn which is like 260 miles away. Obviously, the postulated lines of sight will almost always exceed the personally observed lines of sight thanks to the tricks of atmosphere, climate, and light refraction........

Glad to see people keep commenting on this topic!

Scott
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This map- http://www.heywhatsthat.com/?view=BS5JALP9 -doesn't show much in that direction, a couple of spots in the desert near Big Piney.

That site is interesting, but it appears that it isn't comprehensive at all, but just points out a few points. For example, after checking several Uinta peaks it only list two peaks in the Wind Rivers as being visible. This is far from true as several peaks in the Wind Rivers are actually visible from the peaks I checked.

Another case in point, check out MOKBA's photo looking east from Lookout Peak:

http://www.summitpost.org/image/413768/ ... ut-pk.html

Coodinates are 40.8349 and -111.7176

Try to find Gilbert Peak (almost due east, but not quite and would be the most distant peak labeled in the photo) from Lookout Peak on the heywhatsthat site.

If you can't see the Tetons from the Uintas, I wonder what they could be? You can definately see above the Wyoming Range.

Next, I can check views to Wyoming from the Uintas (Kings Peak?). Viewing peaks in the Wind River Range looks more likely than the Tetons, but the Wind Rivers' distance from Kings would not be record-setting unless I can get something on the north end.

So I need to know if Kings Peak a good viewpoint to use. Or are there other possibilities that should be checked?

No, Kings wouldn't be a good one to try unless you want the Wind Rivers. Try something like Lamotte Peak. Lamotte is almost straight south of the Tetons. Kings Peak is more easterly. Also, try it in the opposite direction.

brendon

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Have you turned on the visibility cloak?

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