They are then further filtered out partially by dark adaptation of the photoreceptors lying beneath the capillaries. Your brain automatically filters out the shadowing lines of these capillaries (similar to the way you cannot see things at a certain angle/point in your visual field while focusing at its center). Blue light, (at a wavelength of about 430 nm) is absorbed by the red blood cells which fill the capillaries. The dots themselves are the result of white blood cells moving along capillaries (which is the reason for their color), in front of the retina. The dots are highly conspicuous against a monochromatic blue background typically making up one's view of the sky - as the sprites themselves are small and white, and their trailing tails are usually darker, near grey. Most people can see this phenomenon in the sky, although it is rather weak, and many people do not notice it until asked to pay attention to it. The left and right eye see different dots someone looking with both eyes sees a mixture, as the images are laid over one another in the subconscious observational process. The dots appear in the central field of view, within 10 to 15 degrees from the fixation point. They briefly accelerate at each heartbeat. Often described as "seeing stars" The dots may be elongated along the path like tiny worms, and The speed of the dots varies in sync with the pulse of the one experiencing them. Some of them follow the same path as predecessors. The dots are short-lived, visible for a second or less, and usually travel short distances along seemingly random, often curved paths. It's the appearance of tiny bright dots (nicknamed by Richard blue-sky sprites) moving quickly along squiggly lines in the visual field, especially when looking into bright blue light such as the sky. Richard Scheerer first drew clinical attention to this phenomenon in 1924. The blue field entoptic phenomenon or Scheerer's phenomenon (named for the German ophthalmologist Richard Scheerer) is a physiological phenomenon that takes place in the retina. They can appear anywhere from being faint, dark spots which seem to move along tracks slowly and which seem to have a whitish color at their central points of travel - too thick and bright and made up of similar whites and greys, and moving quickly along those same pathways. But eventually, you will look up again at the blue, or the grey, of the sky - and that is when they will once more become significant and noticeable. Thinking they are gone, you might continue to go on about your day. You may not see any, anymore - or you may find there are only one or two at the corners and edges of your vision. When you look back to the ground, and your vision is not placed flatly against a solid color, they are significantly less noticeable. No matter where you move or seem to look, now that your attention has been called to them, you are starting to notice them. Each heartbeat, they go soaring through a small spot of your vision before dissipating and there are hundreds of them - all moving at once. Racing back and forth in your vision in sometimes repeating patterns - but also sometimes seemingly at random with just a few repeating patterns, are these little white squiggly lines. Picture this: you're standing in a field, on a bright sunny day when suddenly you look up into the cloudless, clear blue of the sky.
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