Retro Technology

Perhaps confusing for today's audience. Data was routinely stored on tapes and transmitted over distance. The unfamiliar part for an.audience of the time would have been sending pictures.

From the explanation, what I gather is that the photo was basically bromen down into points where an average darkness was derived by passing a needle over the photo's conductive surface and reading the voltage. That voltage was converted into a darkness level and recorded on the tape, which was then transmitted as usual.

At the other end, a light was shined through the tape, concentrated on a point of the new film, which was moving in exactly the same way as the original had been moving under the needle. Obviously, more holes would amount to more light. It's basically the same way a CRT television works, only doing it with light manually a single image at a time.

In effect, they reduced the image from the conaiderable resolution of the original negative to a substantially smaller digital resolution with only a few levels of greyscale, then transmitted that. The fuzzy analog nature of the film used to reconstitute the image probably made that look quite a bit better than you'd expect, but either way that was then converted to a series of black dots using halftone screens for later printing in the newspaper. It's interesting to me that it wasn't converted to halftones first. You'd think that would objectively contain less data to transmit, and could be transmitted im black and white rather than greyscale. Perhaps the resolution of the image after being processed that way was technically more or the same amount of information. More likely, I suspect it was fast enough, and the transmitted photo was usable for more than just printing on a low quality news press.