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Talk:Diffraction spike

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Latest comment: 1 year ago by 194.254.113.72 in topic Fourier transform

Spikes?

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so... why are there spikes in the stars in the corner of the image? i'd have thought the light from these doesn't pass near to the struts, and thus wouldn't be diffracted by them? --Arkelweis (talk) 17:26, 20 July 2010 (UTC)Reply
Each individual field point (think pixel on the image) when it enters the telescope fills up the entire aperture (to first order). The reason you make a really wide telescope is to gather more light, it's not correlated to how wide a field-of-view you have. So each field point is affected ~equally by those struts. 162.18.172.11 (talk) 20:47, 2 August 2010 (UTC)TimReply

Generality

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I think this page should be made more general, as it seems to assume that only Cassegrain telescopes exhibit diffraction spikes. They aren't limited to 4-strut geometry, and the suggestion that refractive systems don't have them is false (depending on how general you want to get with 'spike', cameras that use an iris will show 'spike-like' features in the diffraction).162.18.172.11 (talk) 20:52, 2 August 2010 (UTC)TimReply

Diffraction spikes versus lens flare?

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I think some reference to lens flare could be included to distinguish diffraction spikes. They seem they can be easily confused. Mal7798 (talk) 03:46, 28 August 2016 (UTC)Reply

Eyelids and Eyelashes.

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Why does this article limit itself to photographs?

The effect is also present in the human eye - where bright lights cause the same effects due to diffraction through eyelashes and eyelids.

It's more general than this article suggests.

12:24, 17 November 2017 (UTC)

Further explanation of the so-called "diffraction spike"

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I believe that diffraction per se is only part of the explanation for the so-called "diffraction spike".

If the aperture has n-fold rotational symmetry (e.g., 4-fold, 5-fold, or 6-fold), then because the mechanism is not circularly symmetrical, after it opens and closes, the photo-sensitive substrate will necessarily be exposed to a non-uniform amount of light in its different parts. This is what I think is the main reason for the "starburst" shape of the patterns caused by light sources in space. 2601:200:C000:1A0:217F:F562:B16A:21E1 (talk) 02:35, 12 July 2022 (UTC)Reply

Fourier transform

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What does the phrase "diffraction spikes [...] are the Fourier transform of the support struts" mean? How does one "Fourier transform" struts? 194.254.113.72 (talk) 11:59, 22 May 2025 (UTC)Reply