Talk:Circumzenithal arc
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"Artificial circumzenithal arc" chapter is misleading
[edit]The resulting arc of the experiment is: Bent the wrong way (open towards the "sun", not the zenith) and colours are in inversed order (blue nearest to the "sun"). I think what has to be considered is that the real arc is formed from crystals at many different positions (not only different orientations). The colours are then swapped in their order as the light rays from different drystals cross, just like the rays from different water drops in a rainbow. The shape is a bit more complicated. As far as I could reproduce it using four glasses, their arcs cross at some point (where the observer stands and looks up). Glasses placed at the outside have to be moved towards the observer/zenith so that their arcs cross at the same point as the inner glasses. Therefore you get an arc bent around the zenith, as the glasses/ crystals you see have to be moved on a circle around the zenith to make them visible at the point of observation.I think this is how the arc is formed. The single glass method is definitely not a complete model, I think this should atleast be mentioned somewhere. 93.216.41.252 (talk) 18:55, 25 June 2017 (UTC)
2 events
[edit]What are the odds of this phenomenon appearing on 2 separate dates celebrating the funeral and family gathering celebrating his life ? This happened later. I refer you to wikipedia Thomas G Cavanaugh tragic hockey playes BarbaraaWilson (talk) 19:50, 22 July 2017 (UTC)
An entoptic phenomenon (Caes arc) which looks like a small Circumzenithal arc
[edit]Here's something I discovered in 1978, age 14. I call it the Caes arc. It is only noticeable when one is looking at an angle of, say, 25 degrees away from a very bright white pointlike lightsource (dark background). The phenomenon looks like a small Circumzenithal arc with angular diameter of something like 5 or 6 Full Moons in a row. The colors of this arc are the "negative" of the commonly known spectrum. The convex side of this entoptic arc is aimed at the lightsource (just like the Circumzenithal arc). Around this arc there's a field-of-view filling cobweb of dark blood-vessels (the Purkyne tree). To get a perfect view of the entire entoptic phenomenon (the Caes arc and the field-of-view filling cobweb) one should try to "glide" the center of vision around the pointlike lightsource. Once you get the "trick" to perform this unusual technique, you shall be surprised! (so I was back in 1978 at age 14). And... no, I'm not a drugs-addict, and... yes, I am an optics-freak. Now, what I really want to know is, if my discovery of 1978 was already known by someone else, say J.E.Purkyne, or not? Is it somewhere described in a scientific journal, such as the J.O.S.A. (Journal of the Optical Society of America)? Is it related to the entoptic phenomenae Haidinger's Brush and Maxwell's Spot? DannyJ.Caes (talk) 14:58, 3 August 2019 (UTC)