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Off in the distance...

A forum to post any lighthouse pictures you'd like others to see. Feel free to talk about lighthouse photography. Lighthouse-related photos (such as LSS and lenses) are also welcome.

Postby Gary Martin » Sat Oct 11, 2008 12:08 pm


When I got to Ft Niagara last week, you could see buildings on the skyline out across Lake Ontario. The buildings are downtown Toronto, with the prominent CN Tower to the left. According to Google Earth, as the crow flies from where this was shot (300 mm), it's 31.96 miles to Toronto across the lake.

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Postby LeadingLight » Sat Oct 11, 2008 1:46 pm


We are wondering here if it is the real skyline you see, or a mirage. I lived at the coastline of Terschelling Island for a while, and in specific weather conditions I could see the mainland, though theoretically that was impossible because it should be under the horizon.
The distance between Gary and Toronto is about 30 miles. Presuming that it are English miles, that is about 26 nautical miles. The list of lights has a table where you can find the geographical range of a lighthouse. That is the range that a light would have in theory, when there are no weather conditions disturbing it. To get a geographical range of 26 NM, the light should have an elevation of 140 metres (459 ft). So the other way, buildings have to be more than 140 metres high, to be visible from 26NM. With the CN Tower of more than 550 metres (1815 ft) as a reference, it is still possible that it is the real skyline and not a mirage. So the conclusion.... we're still wondering :?
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Postby Gary Martin » Sat Oct 11, 2008 2:41 pm


Interesting question, Frans. With the CN tower, that clearly isn't a mirage. Some of the small buildings to the extreme right have to be a mirage as they're separated from the horizon line when you look at the image at 300 dpi. I think the bottom line is that we're dealing with a mixture of real and mirage.
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Postby LeadingLight » Sat Oct 11, 2008 10:28 pm


I thought I recognized the image of buildings seperated from the horizon, so that brought up the question. Until I lived on the island I never knew mirages were real. I only knew the fata morgana drawings of thirsty people in the desert, that saw what they wanted to see. It's interesting stuff.
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Postby Gary Martin » Sun Oct 12, 2008 4:46 am


A couple of times a year there is a mirage from Chicago visible in St Joseph, Michigan about 70 miles away. I've not seen it but have been told you can read the Coca Cola sign on one of the buildings as clear as a bell.
Last edited by Gary Martin on Sun Oct 12, 2008 7:24 am, edited 1 time in total.
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Postby Leah Loar-Mays » Sun Oct 12, 2008 4:52 am


And I'm left wondering how the heck one manages to photograph a mirage?????? :? :roll: I find it much easier to believe that you can actually SEE the skyline 30 plus miles across the Lake...............
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Postby LeadingLight » Sun Oct 12, 2008 2:06 pm


Photographing a mirage is not more or less difficult than photographing anything else. There is no magic in a mirage, it is just an atmospheric effect that you can see and photograph. http://en.wikipedia.org/wiki/Mirage
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Postby Hersh » Sun Oct 12, 2008 2:32 pm


Leah, anything you can see, you can photograph. Except for vampires of course. Everyone knows you can't photograph them or see them in a mirror.
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Postby Leah Loar-Mays » Mon Oct 13, 2008 5:56 am


Thanks for that tip, Mike.............. :roll: :lol:
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Postby Leah Loar-Mays » Mon Oct 13, 2008 6:03 am


I guess I have always been under the mistaken impression that a mirage was not real in any sense, but imagined by someone longing to see something or someone. An image created by atmospheric conditions is a true phenomena.

Thanks for the info!
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Postby LeadingLight » Mon Oct 13, 2008 11:20 am


That's a Fata Morgana, but it is in fact based on the same atmospheric effect, that is very strong in deserts (like on roads on a hot sunny day). The thirsty man really sees the oasis, but due to the mirage it looks close, but may be 30+ miles away, which is quite a distance to move on your knees without a drop of water :?
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Postby island » Tue Oct 14, 2008 8:11 pm


Some many months ago this phenomenon was discussed in the Lighthouse Technology section on this board. Under certain admospheric conditions (clean and cool air ) light bends or refracts over the horizon and objects beyond the geographic range of visibilty can be readily seen in detail during daylight. At night the light from a lighthouse or other sources may likewise be visible well beyond the geographic range of visibility. This atmospheric refraction of light is most apparent when air turbulance is minimial in early morning or late afternoon and/or at night .

The differs somewhat from a fata morgana which is caused by distortion of light by alternate layers of hot and cold air and would most often be present during mid-day heating of the air by the sun. An example of this is an island or land mass in the distance that appears to be suspended above the water or land below.
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