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(meteorobs) Counting rates
It strikes me that this counting discussion needs a jolt of common sense. Lets's use the analogy of the animated movie. If someone knows different information, please correct me....but the limit, I believe, of the ability of the human eye to detect separate images is about 17 frames per second....the lower limit of the visual cortex to observe smooth motion. In other words, when one looks at an animated film, the "motion" which is composed of separate still images, must be created by screening more than 17 images per second. (61,200/hour).
Motion pictures developed from many different traditions, including theatre and magic shows, but also from the Victorian fascination with the phenomenon of persistence of vision. The human brain retains an image for a fraction of a second longer than the eye actually sees it. That is why the world doesn't suddenly go black every time you blink. When you watch a movie, what you are actually seeing are individual still frames of film projected at 24 frames per second. Each of these frames is separated by darkness, so you are sitting in a dark theatre about half of the time. The images are discontinuous; that is, all of the action that happened between the frames is not represented. Because of persistence of vision, what you perceive is one image blending into the next, giving the illusion of movement and continuity. The dark spaces are "ignored" by the brain.
But this is at the level of what the eye will perceive....not what can be recorded.
Even merely speaking the magnitudes into some sort of recording device "Mi-nus se-en" ...mi-nus three", or punching a keyboard, introduces other levels of human physiology that render counting above about one meteor per second ("one-a- thousand, two-a-thousand.....") pretty impossible, especially for long observation periods. And this leaves out the matter of accurate judgement on magnitude and duration, color, and path.
I think that when you get to these densities you will have to admit that some sort of mechanical device with a film record is the only way to achieve any sort of counting accuracy.
If one could consider the meteor a kind of strobe light....the very best, and fastest film for recording strobe images is mylar based. Remember the National Geographic hummingbird photographs? They used strobe technology--and mylar film.
Just a suggestion....
Susan Miller, Philadelphia
rank amateur, poet, out of the box thinker
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