Unreal Nature

January 29, 2010

How Thick is the Present?

Filed under: Uncategorized — unrealnature @ 7:08 am

No one has lived in the past and no one will live in the future.

The present is the form of all life, and there are no means by which this can be avoided.

Jean-Luc Godard, from Alphaville

The first section below is from Flashback: The Photography of Dr. Harold Eugene Edgerton; an interview with Gus Kayafas in Aperture 158 (Winter, 2000):

This is a photogram, a cameraless picture. It’s a 30-calibre bullet and you’ll notice these black spots at the top right; these are where the bits of Plexiglas actually punched a hole in the film. It was a sheet of 8-by-10 high-contrast film. It’s a point-source flash, so just as you get sharp shadows cast by the point source of the sun, this would cast very sharp shadows. In America, often when you’re driving, you’ll see a heat differentiation coming off the asphalt and it looks like a mirage, like water because that’s the way our brains read it. The light is being bent by that change in the density of the air from the heat, and that’s what’s happening here. The change in pressure creates the shockwave, and the light actually gets bent, so it ends up not exposing the film evenly. There’s a secondary wave of shockwaves, and that’s the one that hits the microphone to set the flash off. There is a piece of Plexiglas, in a vise with a microphone, with a bullet going through it. Essentially, instead of a photogram made like a contact print — because this is a point source light — the film is about ten or twelve inches away from what happens. This is something Doc developed during World War II to study projectiles and how they worked. This led to his interest in the speed of sound in different media.

The next section is from an online excerpt (yes, I am excerpting an excerpt.) A Tenth of a Second: A History by Jimena Canales:

… Try this experiment with a cinematographic projector. If successive frames pass at a speed exceeding the tenth of a second, the illusion of movement appears smoothly. Reduce its speed, and the illusion disappears. Look closely at a rapidly moving target and try to time the precise moment when it crosses a specific point. Compare the moment with somebody else’s and you will see that each of your determinations will probably differ by a few tenths of a second. Step on the brake of your car when an obstacle appears in front of you, and despite your best efforts, a lag time, close to a tenth of a second, will haunt your reactions. Try to read as many words as you can in ten seconds, and you will notice that the number is about a hundred: one word every tenth of a second. Time yourself while talking, and you will see that the time needed to pronounce each syllable will never be less than a tenth of a second. Analyze the electrical rhythm of your brain, which, when at rest, will average ten cycles per second. Study a “perceptual moment” and find that it lasts about this same amount.

… As scientists introduced the language of modern communications theory, employing terms such as “message” and “transmission,” they increasingly referred to the tenth of a second. The mid-nineteenth-century descriptions by the influential scientist Hermann von Helmholtz are characteristic: “When the message has reached the brain, it takes about one tenth of a second, even under conditions of most concentrated attention, before volitional transmission of the message to the motor nerves enabling the muscles to execute a specific movement.” “Self-consciousness,” he noted, lagged “behind the present” by an amount equal to “the tenth part of a second.” By the 1880s it was common knowledge on both sides of the Atlantic that “the time required by an intelligent person to perceive and to will is about 1/10 of a second. … After allowing for the time required to traverse all of the nerves and for the latent period of the muscles, there still remains about 1/10 second for the cerebral operations.”

… As scientists who investigated the tenth of a second increasingly treated the senses as instruments, they started to ask how bodily differences affected knowledge. Bodies were not the same, and this could have important repercussions for science. If instruments were compared to the senses, how could one be assured of the precise moment when they ended and perception began? Questions of time and its relation to space became entangled with questions relating to bodies, body types, and body parts.

… How do scientists determine the length of a ruler, the moment of contact between celestial bodies, the speed of fugitive events and occurrences within a tenth of a second?

… Instead of focusing on local political and social aspects of modernity that affect the place of numbers in society this book is centered on the moment of measurement. All measurements (including “measurements of distance”) require a “making present” that is intimately connected to problems of a temporal order.

“Making present.” *holding my head in pain*

After all my previous posts in this blog about how the present is always killed in the moment of the making of a photograph … Maybe it’s okay to measure it after it’s dead if it’s still fresh.

-Julie

http://www.unrealnature.com/

2 Comments

  1. The “present” says: “Why should I be different than a rabbit?”

    Comment by Dr. C. — January 31, 2010 @ 11:57 am

  2. “We all live in a tenth of a second world.” A. E. Kennelly, chief laboratory engineer for Thomas Edison.

    Comment by Jimena Canales — February 12, 2010 @ 12:00 pm


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