How did they used to print pictures on newspaper before computers?

Question

Before they had computers to print the newspaper, how were pictures printed for newspaper?

Answer 1

with a printing press

Answer 2

Pictures were transferred to a coated metal sheet, which reacted the same way as printing photos onto paper....the coating absorbs more or less light, according to the image. For photo printing this is then developed in chemicals to give a visible image.

For printing plates, a mesh pattern is laid between the negative and the plate. When the plate is etched, the metal gets little holes of varying depths representing the dark and light on the photo. The printing ink fills these holes, but the shallower smaller ones transfer less ink to the paper, giving the lighter parts of the finished printed picture. (THe mesh pattern breaks up the areas so they don't "bleed" into each other).

For colour printing, three plates are made (cyan magenta and yellow) (sometimes a fourth black one for crisper images) and overprinted on each other.

In the 1960s and 70s news photos were transmitted around the world by a method similar to teletype, which produced small dots of varying density on a negative film attached to a revolving drum. This was then used to make the printing plate.(poor quality images though).

These methods are still used for the actual printing of newspapers and magazines...only the writing and composition are done by computer. The finished images still get transferred to a metal sheet (in reverse) which is inked, so the image tranfers to the paper.

Answer 3

How far back to you want to go? In the old days I think that they used to etch images onto printing blocks with acid or something like that, or they used engraved plates for things like logos that were used regularly, but that was a loooong time ago.