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Why We Didn’t Take Screen Grabs in the 1980s (www.worldcadaccess.com)

submitted 2 months ago by [email protected] to c/[email protected]

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Ralph Grabowski was the technical editor of CADalyst magazine in the 1980s. He writes about how they created screenshots of graphical programs of the time

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[–] [email protected] 16 points 2 months ago* (last edited 2 months ago)

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To get a nice picture, I had to compensate for the problems posed by photographing actual screens of computers. One was glare from the daylight and from office lights; another was the curvature of the computer screen, which in those days were made from cathode ray tubes (CRT); a third problem was setting the correct exposure in the camera to end up with a richly-colored image.

… The glass was curved so that the electron beam traveled the same distance from its source to the screen, no matter its position on the screen.)

To compensate, I came into the office of CADalyst magazine at night, set up my camera on a tripod with a 100mm lens, reduced the f-stop by -2, and used the self-timer to take the photograph. It took, naturally, me a while to get all these parameters correct, as I was working with slide film, which needed to be sent away for processing. It could take a week or two to see if the results turned out -- or not.

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