On a personal note:
My working life:

For about 400 years all printing was done by wooden, steel, or lead type. Or etched metal plates, for line drawings. Now it is all done by computers and lasers. But for a brief time between these two technologies, existed photo mechanical offset printing. This is what I became expert in, working for 35 years. Now a completely extinct trade. 

What is interesting to some modern folks is that what we did was basically a complex analog to digital converting process. When you look at a printed photo, closely, you see dots. Because the press is digital, there is either ink there or no ink. But a painting is analog, continuous, and layered. It was the job of the photo mechanical technician to convert the analog signal of a painting into the digital signal of a printed page.

The single piece of tech at the center of this process, was the "halftone screen", or "stochastic screen". What this was, is a transparent piece of mylar, or other clear film. With very precise dots, but not just any dots, these dots were each gradients. Each dot was at the center opaque to light, then surrounded by concentric circles of increasing transparency. So that when placed between a reflected light source and a large piece of photo sensitive negative film. The more light striking the dot, the smaller the dot on the film.

This then produced on the film a series of dots of various sizes. This film was a negative and would be used to make a positive printing plate. Smaller dots for the lighter colors, more white paper reflecting light off the final printed page. Larger dots for darker colors, more ink on the page. Now these dots were arranged in a regular grid, normally 360 dots per inch, sometimes a lot less, sometimes more dense. So from the readers normal distance from the page one could not see any dots. This gave the illusion of a continuous tone. 

Thus taking an analog art piece, converting it to digital for printing, and then fooling the brain into thinking it was continuous and analog.

Printing full color is another story, imploring four of these negatives full of dots of varying sizes. And printed on top of each other. In four consecutive print passes. This was called the CMYK method, cyan, magenta, yellow, and black. Or subtractive color printing. Now for the truly geeky, you might notice that whenever you overlay a regular transparent grid of lines or dots you get a moiré pattern. To avoid this in three of the color negatives the grid of dots was rotated by 30°, progressively, the yellow rotated 15°.  (oh yes it gets pretty complicated).

Now I am leaving a lot out of this story. But I think you get the gist.

Basically I was an analog to digital converter.

Absolutely and totally obsolete.