Talk:Sundial Bridge at Turtle Bay

message: From the Article  "The deck is surfaced with transparent structural glass, with a view of the water below as one crosses."
This is actually incorrect: The Bridge was planned with this in mind, but (at least this is the explanation printed in the newspaper) the clear panels and view of the river below disoriented people so much that the panels were frosted and are now translucent (this shows in the photos btw).
:Stupidly enough, we'd actually need a source for this if we were to change it24.205.34.217 00:53, 26 April 2007 (UTC)
thread_title:  Frosted glass 

message: Could someone explain me the funktion of the bridge as a sundial? I am expert in these things, and I don't know a sundial, which works correct only at one day in the year. The best would be, to give me pictures from the scaled plane and the "gnomon" (is it only the shadow of the top point which gives the information?). 62.204.120.21 (talk) 13:55, 29 July 2008 (UTC)
replies: text: When I saw it two months after the solstice, the dial was crossed by the shadow of the gnomon a little way below the point: see this photo, which I took from the dial. At the solstice, the sun would be higher but I think not enough for the shadow of the point itself to lie on the dial, I'm not sure. It was still quite accurate at that time (within a minute or two), but my guess at the reason it's not perfect year-round is that the angle of the gnomon is not sufficiently tilted: it's 42 degrees from vertical, whereas to match Redding's latitude perfectly an angle of 49.5 degrees would be needed. —David Eppstein (talk) 20:19, 15 August 2009 (UTC)
replies: text: Actually, the latitude of this bridge is 40.5 degrees, not 49.5.  The source of the 42 degrees is an Architectural Digest article no longer available, cannot verify this or the article's source. Jaguarmountain (talk) 19:43, 9 October 2022 (UTC)
thread_title: Request for explanation

message: Every object and natural feature on the surface of the Earth provides the hour with exact precision one day (the solstices) or two days (all the rest of the days) every year, and that is not reason enough, properly speaking, to say that everything bathed by the sun is a sundial. In that case, any tall building has all its corners acting as gnomons, and the largest sundial on earth would be the mountain rising higher over its surroundings. Sundial bridge is a beatiful example of a bridge, with some solar effects, but it is not a sundial, not because the author did not know how to do it, but because he did not intend to. We can not misinform people. For the Sundial Bridge to be a true sundial, the gnomon should be alineated with the Earth's axis, and it is not.  —Preceding unsigned comment added by 83.61.157.84 (talk) 22:05, 12 December 2009 (UTC)
replies: text: This particular object is named a sundial, was designed to be a sundial, and features a dial display. It is also, per the discussion below, accurate months away from the solstice. I see no justification for removing the sourced claim that it is the world's largest sundial and replacing that with an unsourced opinion that it is not really a sundial because it fails to meet some imaginary standard that is not applied to other sundials (the gnomon being precisely aligned to the latitude — note that most garden sundials are similarly misaligned). I'm reverting again. —David Eppstein (talk) 22:19, 12 December 2009 (UTC)

text: No. You need a source stating that this particular object is not really a sundial; anything else is original research by synthesis. And if you find such a source, you still don't get to rip out the sourced claims that it's a sundial and substitute them by the opposite: what WP:NPOV demands in that case is that you report both sides of the controversy. —David Eppstein (talk) 23:35, 12 December 2009 (UTC)

text: You are arguing as if this is a matter of opinion and that you need to convince me that my opinion is wrong. That is an invalid basis for editing on Wikipedia. We need to go by what the sources say even if we disagree with what they say. We have reliable sources that say that it is a sundial. They may themselves be incorrect, but that is what they say and that is what we have to report. If you provide sources contradicting them, then we can at least report on the contradiction, but so far all you have done is argue and that is completely unproductive. See WP:Truth. —David Eppstein (talk) 16:06, 13 December 2009 (UTC)

text: Lack of evidence is not evidence of absence. But if you can find a sourced claim that some other specific object is the world's largest sundial then we can at least say something like "the sundial bridge has been claimed to be the world's largest sundial, however, X is larger." PS since I've run into the limit on how many times I can revert, and in any case since this repeated edit and revert cycle is highly unconstructive, I've asked on WP:Content noticeboard for a third opinion. —David Eppstein (talk) 16:21, 13 December 2009 (UTC)
replies: text: Taipei 101 is taller, and is a sort of unsatisfactory vertical sundial with a relatively small dial plate in Millennium Park which can be used only in the afternoon. Binksternet (talk) 18:09, 13 December 2009 (UTC)
replies: text: The North American Sundial Society lists the Calatrava Sundial Bridge in its links on the web. They define gnomon as being either polar-pointing, horizontal or vertical. They do not define style as a polar-pointing gnomon in the way it was used after the late 16th century—instead they define style as the line in space which is used to indicate time on the dial plate. Binksternet (talk) 18:34, 13 December 2009 (UTC)
replies: text: In 2005, Dr. David P. Stern was asked whether the Calatrava Sundial Bridge is a sundial, and he said that it would be an accurate sundial if the center of the dial plate were located in a spot where a line from the top of the bridge pylon met the ground at an angle of 40.6°. Stern said he did not know if this was the case. Binksternet (talk) 18:41, 13 December 2009 (UTC)
thread_title: Sundial or not?