The earliest surviving camera photograph. The original (left) and the colorized enhancement, turned right-side up (right) (Wikipedia) |
Note: Imagine a time before photography, when the only way to record someone's appearance was by hand (drawing, painting, etc.) Imagine all the places we can see today because of photography (and her daughter, videography). This technology has changed everything.
Get Ready: Can you think of any photographs you've seen--or a person, or a place--that have really moved you? Pictures of an ancestor, or a far away place--or even you as a baby?
In the 1820s, a Frenchman with the unlikely name of Joseph Nicéphore Niépce invented a phenomenon the lineal descendant of which you likely have in your hand or your pocket at this very moment. I'm speaking, of course, of the heliograph.
"The WHAT?!" you may ask. Well, helio- means "sun," and -graph means "write." As subsequent inventions moved away from using the sun as a source, a decade or so later the generic term for light, phos-, became more popular. Yes, Niépce is credited with creating an image using the sun, rather than the hand, to make an impression: the first photograph, ancestor of the one you can now make with your smart phone.
Here's how it happened: Niépce was looking for a way to produce copies of printing plates (a process called "photogravure" or "photolithography") by means of a material called Bitumen of Judea, a naturally-occurring material that was a light-sensitive.
Applied to a pewter or stone plate, the bitumen would harden when struck by light, remaining pliant where it was not. The plate was placed on one wall in a darkened chamber (in Latin, a camera obscura, from which we take the word "camera") with a small "pinhole" in the opposite wall, which served as a lens. (You can easily duplicate this device. Remove one end of a box and cover it with thin paper; place a pinhole in the opposite end of the box. In a darkened room, aim the pinhole at a bright image, and, if the distances are correct, see it reproduced on the paper.)
A camera obscura ("dark room") at work (Wikipedia) |
Niépce would then take the plate with its bitumen of varying hardness (called a "photoresist") and apply a solvent--such as oil of lavender--which would dissolve the soft areas and the pewter or stone underneath, leaving the hard bitumen and the substrate under it intact.
The bitumen was then thoroughly removed, and the plate (with its negative image) used in printing.
Exposures by this process were long--at least eight or nine hours, but sometimes several days. Naturally, heliographing moving subjects was impossible. In fact, the process was often used simply to copy other images and produce printing plates from them.
--------Read more: https://en.wikipedia.org/wiki/History_of_photography
Practice: Match the term to its definition below:
- exposures
- generic
- lineal
- negative
- pewter
- pliant
- solvent
- subsequent
- substrate
- unlikely
- in a direct line
- a soft metal alloy made mostly of tin
- having light and dark reversed
- periods of opening to light
- the layer underneath something
- not specific
- improbable; surprising
- following after
- a substance that dissolves something
- flexible; soft
Answers are in the first comment below.
Submitted to the Shenzhen Daily for November 16, 2020
Answers to the Practice: 1. d; 2. f; 3. a; 4. c; 5. b; 6. j; 7. i; 8. h; 9. e; 10. g
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