Life Before Cell Phones 4 of 5: Taking Snapshots (Without Having to Lug Around a Digital Camera) in the Days Before Smartphones
Back in the days before smartphones, in order to take a “snapshot” of your friend—without having to endure the inconvenience of lugging around your Sony digital camera everywhere you went—you had to carry under your armpit a silver-coated copper plate (sensitized with chloride of iodine and chloride of bromine); have your friend sit in a spot where there is plenty of light; find a way to expose the copper plate for only a few seconds (you might need to quickly improvise some kind of camera-chassis); and then take the plate to a darkroom and bring out the image with heated mercury.
Not done yet! Then you’d need to “fix” the image by bathing the plate in hyposulphate of soda. After that, you’d have to wash the plate in distilled water. Once it dried, you’d have an old-fashioned “daguerreotype” of your goofy friend giving you the finger.
If you want to further your education, please check out the other “lessons” in this series. And be sure to check back in for the final lesson!