![]() As long as you learn from it, and we learn what useful things you want to say, nothing at all to worry about. I tried to make an initial explanation, but then someone beat me to it and I made a fool of myself on the page trying to add a comment where it didn't go. Īdd a comment! ⋅ add a topic (use sparingly)! ⋅ refresh comments! Discussion Transcript Bad news for exoplanets: it turns out those diffraction spikes are real. The title text also claims that the spikes produce sufficient light and heat to disrupt seasonal (and perhaps even diurnal) patterns on planets that come close enough to them, but this is not something we experience on Earth. This would make our own solar system exceptionally fortunate, given the number of planetary bodies that remain whole, though it could perhaps serve as an explanation for the Asteroid belt, being remnants of formerly destroyed planets. The title text suggests that a planet would have to be particularly lucky to avoid encountering one of these spikes during its lifetime. Additionally, they appear to nullify gravity - preventing the halves from recombining and allowing them to maintain their shape. The spikes have sufficient energy and coherence to slice planets that intersect them, rather than merely bludgeon or vaporize them. The comic feigns that these artifacts are real spikes of stellar matter extending from the stars being viewed. They've become especially well known lately because they're quite prominent in images from the James Webb Space Telescope its bigger spikes are due to the edges of the hexagonal mirror sections, not the struts. ![]() In telescopes, they are often caused by the support struts of the secondary mirror in the telescope. The terms should not be used interchangeably.Title text: Even if a planet is lucky enough to have a stable orbit that weaves between the spikes, the seasons get weird whenever it passes close to them.ĭiffraction spikes are visual artifacts that appear to extend from light sources, mostly when viewed through a reflector telescope. What is the difference between diffraction spikes and lens flare and are the two terms interchangeable?Īs can be seen above, the two are different phenomena that can be photographed together or separately, pending circumstances and goals. This can be done with a lens hood, a scrim, a sheet, your hand - really just about anything. If trying to reduce flare, the best thing to do is cast a shadow over the lens and block the light coming from the light source. So too does using older/cheaper lenses that lack decent anti-reflective coating). My own experience has led me to conclude that haze is most often seen when the light source is just out of the frame with its light coming across the lens, while visual artifacts can be exacerbated by getting the light source within the frame but still coming in at an angle (use of wide angle lenses helps here, if you're trying to go for artifacts. It can manifest as visible artifacts within the captured photo or as a contrast-robbing haze across all or part of the image.įlare is caused by very bright light sources coming in from a shallow angle to the lens: The smaller the aperture, the longer the spikes.įlare is caused by light reflecting off of the internal surfaces or elements within the lens. In order to elongate them, smaller apertures must be used. ![]() At large f-stops (such as f/2.8), the aperture approaches a more perfect circle and the spikes may not exist or may be too small to see in comparison to the point light source. As can be seen above in the last example, a perfectly circular aperture does not produce any clear spikes. The length of the spikes is directly related to the aperture used. ![]() So, if the aperture has an even number of blades, then the number diffraction of spikes appear to be equal to that number of blades, while with odd-number designs, the number of spikes is two times the blade count. Each edge produces a spike, but due to the symmetry of even-number bladed apertures, these spikes overlap. The number of spikes is directly related to the number of straight edges available in the aperture. This causes the spikes that bleed out from point light sources. Diffraction causes light to spread out, when moving through the aperture of a lens, perpendicular to the straight edges of that aperture. ![]()
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