Talk:Electric Brae

Explanation

What is the explanation for this phenomenon? Thanks. Martinevans123 (talk) 19:18, 6 August 2012 (UTC)

The gradient of the coastline against the level horizon causes the slight-downward hill to look like a steep-upward hill.

For as long as I can remember it's been referred to as an "Optical illusion" but anyone who's seen it and now understands what's happening would realise it must be convincing them as more of a mental illusion. There's no tree-trunks or other vertically standing objects so the coastline is the brain's only reference point for Up.vs.Down. Fortunately brains also have sensation from the Inner Ear, and I presume this to be the alarm bell that creates the eeryness. People rarely hang around. The term "nothing to see" is banded about, however it's said locally in a context seemingly to disuade visitors. It took me 3 half-hour visits to get my head round any of this. Any longer than half-an-hour and I didn't want to see it anymore. On my third attempt I started off by spinning round till I was dizzy and waiting for my vision to return to normal, each time facing a different direction. Facing away from the coast made me see the top of the hill properly, although it's virtually impossible to see the bottom of it without also seeing the coast, so would either need something to tunnel my vision or block the coastline for that. Steve Corry (talk) 19:42, 6 August 2012 (UTC)

Find a reliable source (not just you) who says this and link to it - that's all which is needed. Your statements and photos and experiences, no matter how convincing they are, are not enough. - DavidWBrooks (talk) 19:57, 6 August 2012 (UTC)

(ec) I think you must have a very sensitive Inner ear, as I don't think sense of balance is usually mentioned in the explanation of visual illusions in general or of this hill in particular. But, however strong your own personal experiences are, they count for nothing at wikipedia, I'm afraid. What is needed is a reliable published work which also gives this explanation. Martinevans123 (talk) 19:58, 6 August 2012 (UTC)

I'm not sure whether a 2-dimensional picture can really convey the sensation, or illusion, or sensory phenomenon, or whatever we call it, even with the best verbal description. But that's not to say that it couldn't be usefully added to the article, if it's location could be verified. Martinevans123 (talk) 20:05, 6 August 2012 (UTC)

It depends on whether the camera is being suspended in a gyroscope fashion or held by someone who acquired their perception from the horizon+coastline. However the difference between both recordings simply adds to the (already overwhelming) evidence that there is an illusion in play but not where. Steve Corry (talk) 20:16, 6 August 2012 (UTC)

I'm not sure how a reader could tell how the camera, which has taken any image, has been suspended. But I am sure that there is no dispute over whether an illusion is "in play", which can be seen, or experienced, by most people - after all, that's why this article exists. Martinevans123 (talk) 20:22, 6 August 2012 (UTC)

I'd hoped that I could publish the answer on Wikipedia without requesting anyone's efforts, not least yourself David or John. However if it's not to be then I'll leave it. I appreciate David's advice and may return one day having been able to respond. Thank you. Steve Corry (talk) 20:39, 6 August 2012 (UTC)

I hope you find something. The image at this site [1] looks quite convincing to me - that road looks very much like it's going downhill. The text says this: "Although the road slopes gently downhill, from the land towards the sea (travelling east to west), it seems that human perception judges such things relatives to the surroundings of the observer, and visual cues such as the angles of the hillsides in the background fool the mind into seeing the road apparently slope downwards from sea to the land... The view should appear to show a road that slopes downhill – away from the photographer – but actually slopes downhill towards the photographer." But maybe you could take a picture just like this one? Martinevans123 (talk) 20:56, 6 August 2012 (UTC)

Unfortunately it's 50 miles from home and I'm a cyclist. I was at a caravan park less than 5 miles from site, so future visits are less practical. If there is a next time then I'll hopefully be better prepared for it. Steve Corry (talk) 21:01, 6 August 2012 (UTC)

That's very noble of you. Nobody here doubts your sincerity or enthusiasm. Meanwhile, I'm sure we'll keep looking for better sources for the explanation for the illusion. Martinevans123 (talk) 21:09, 6 August 2012 (UTC)

I appreciate your effort. Thank you. Steve Corry (talk) 21:13, 6 August 2012 (UTC)

When rotated just 3°CCW the image [2] looks uphill instead Steve Corry (talk) 21:07, 7 August 2012 (UTC)

Assuming vertical to match the post in this photo it would need rotated by <1°CCW whereas assuming vertical to match the parking sign would require rotation of >3°CW so they counteract each other's ability to correct perception.Steve Corry (talk) 21:18, 7 August 2012 (UTC)

That's very interesting about the effect of small rotation. I often crop pictures of church towers and spires, for use here, and am amazed how tilted a spire can look even when the ground (which I know to be flat) shows that he camera was quite level. I think it's impossible to assume what, if anything, is vertical in that picture in the link. We might assume that the camera was level, but we don't even know that. We'd need a surveyor's plumb line in the picture to be sure of anything. Martinevans123 (talk) 22:11, 7 August 2012 (UTC)

Yes, and 2D with a winding road is a challenge too! I wonder though if everyone who photographs the top of the hill does so slightly more CW than they should, and if the converse holds true for photographing the bottom. I'm afraid though that seeing the bottom of the hill is one soley for the brain to present to you. While the footage for the bottom is just as convincing as the top - seeing the bottom for real is unbelievable. Steve Corry (talk) 22:27, 7 August 2012 (UTC)

Altered to help counteract the illusion

Akin to the photo now in the article this one is an attempt to undo the illusion. I've been looking at the pictures too long to be able to tell if there's a difference now though. Steve Corry (talk) 01:50, 8 August 2012 (UTC)

My 'next day' eyes still see a hill going in the wrong direction - but with a lesser gradient than before. There's little conclusion can be drawn from it though other than photos being rotated can negate how the gradient looks. The 'disoriented photographer' theory would need proven with testing from multiple subjects, each taking the same photograph and including the plumb line you suggested but ensuring they can't see the plumb line while they're taking the photograph. Steve Corry (talk) 14:08, 8 August 2012 (UTC)

Down the hill from each side of the road

Among the photos taken I'd overlooked these two, but now see they support the realisation that it's being caused by the coastline. I haven't rotated either of them but brightened each a bit. These were taken immediately after being dizzy and from each side of the road. The plan was to take each from the same position on the road, however the location of the signpost shows that they're a couple of meters out. Steve Corry (talk) 18:47, 8 August 2012 (UTC)

Other gravity hills

As list of gravity hills has now been added, maybe a "See also" section is not required. But, although that list is quite long, there aren't many which have actual articles of their own - I can see only two or three. So should these also be added separately in a "See also" section? Thanks. Martinevans123 (talk) 11:13, 7 August 2012 (UTC)

It's probably best to reference each items' article as links on the Gravity hill article instead. I expect that would then draw attention to this article from the people already studying the others. 82.40.36.180 (talk) 20:15, 7 August 2012 (UTC) (oops) Steve Corry (talk) 20:18, 7 August 2012 (UTC)

Yes, they are linked there already - that's the only way I found them. But if there is only a small number of articles, it might be wise for each to link directly to the others. But let's see if there are any other comments here first. Martinevans123 (talk) 20:54, 7 August 2012 (UTC)

Kilsyth's illusion

Kilsyth: Counter-clockwise perception

In the Kilsyth hills there's a similar illusion. This 10-frame loop doesn't do it justice however shows that the same triangle effect exists underneath its horizon as in Croy Brae and irrespective of whether this horizon is level or not it's now obvious that I'd been holding the camera counter-clockwise of it anyway! Steve Corry (talk) 21:47, 28 August 2012 (UTC)

I passed this illusion twice yesterday on a round-trip to another. In the daylight I could clearly see that the horizon was being rotated counter-clockwise. Later the moonlight illuminated only the sky and the horizon looked perfectly level. Steve Corry (talk) 19:06, 7 October 2012 (UTC)

Road trip, 2012-09: Dunkeld

Dunkeld: Clockwise perception

The Dunkeld illusion differs from Croy Brae and Kilsyth due to having no obvious horizon. When travelling northbound the road looks more downhill than it actually is. When looking behind you (or travelling southbound) the road is almost flat. It's caused by interpretting a false horizon originate from the bending road itself.

I encountered 2 new illusions north of Stirling. One's a road that changed from uphill to downhill before my eyes and the other's a powerful downhill false-flat making my bicycle seem motorised! I intend to re-visit those once the weather improves. Also, there's a huge hill near Dunkeld that should be good for measuring the effect of "rotated perception", triangular in shape and without obstructions. Steve Corry (talk) 22:01, 27 September 2012 (UTC)

The false-flat is located on a dangerous part of the A9 southbound. It's another bending road that's absent of any horizon. When viewing the southbound carriageway from the northbound side it's clearly downhill but while travelling the southbound cycle-lane most of it looks flat. It had my bicycle coast for 2 minutes and 32 seconds. I estimate the effect's strength as matching Croy Brae though it's less impressive due to being downhill only and on a fast-travelled road. Steve Corry (talk) 18:44, 7 October 2012 (UTC)

The uphill-to-downhill is on the A9 northbound however I've since travelled this road twice more and didn't see the effect those times. I either imagined it the first time or there's an unconsidered factor. Steve Corry (talk) 15:48, 14 October 2012 (UTC)

Article improvement

I would like to try and improve this article towards Good Article status. Are any regular editors interested? --MarchOrDie (talk) 20:48, 18 November 2012 (UTC)

Might be an uphill struggle.. or is that downhill? "Obviously an article that has been assiduously improved, even over the past few days, and one that fully deserves to achieve GA status, if the burden could be shared a little." Martinevans123 (talk) 21:20, 18 November 2012 (UTC)

It depends what angle you are standing at, I suppose. --MarchOrDie (talk) 21:42, 18 November 2012 (UTC)

Electric Brae

(moved from User talk:Peter James)

The explanation about the Electric Brae in Scotland is incorrect. The road is clearly steep downhill and this can be checked by a view of the sea. For the Electric Brae to work you must park opposite the RAC box and release the handbrake. The vehicle rolls the wrong way ie. Uphill because at this point the road actually slopes the other way. Because the hill is clearly steeply downhill you have to look carefully to see that,at this precise point there is a slight downward slope. Obviously nothing to do with electricity or magnetism or even a trick of the eye - you just have to look carefully as I did.— Preceding unsigned comment added by 2a02:c7d:3c13:2a00:ec1b:bee1:df03:2db8 (talk) 10:19, 31 August 2021 (UTC)