#1
|
||||
|
||||
How did they made image printings (color especially) before computers?
I can't realize how they did image printings (newspapers, albums, post cards) before the days of "digital printing". First, how did they made the "mold" after the photographic material (film, glass). Secondly, how in the world did they mixed the colours.
|
#2
|
||||
|
||||
I should probably have better details on this since my great-grandfather was a long time employee of one of Chicago's biggest printing operations.
The way I understand it they would process the picture into 3 or more color film pieces if color was desired (but only one for monochrome), place the film over a metal plate with a photosensitive etching compound and place it under light. The compound would etch away the metal at a rate proportional to the amount of light passing through. The etched plate(s) would be loaded into a press and it would get one printing for monochrome pictures or 3 passes for color. IIRC most color printing processes used yellow, cyan, magenta inks...You can see this sometimes when the 3 plates did not align well on an old printed color photo and the three primaries look misconverged.
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
#3
|
||||
|
||||
Here are some of the basics:
https://en.wikipedia.org/wiki/Halftone The original artwork or photograph had to be projected through a cross-hatch of lines to make dots on the printing plate. Since the printing process could only make full ink or no ink, the etching of this pattern varied the size of the halftone dots to get graduated tones. For color, you needed at least cyan, magenta, and yellow printing plates, and almost always a fourth plate called a "key" was printed in black to emphasize the details and also make better blacks, because the color inks were not ideal and would produce typically a brownish black. So, this was referred to as "four color" printing, and still is. Today, programs like Photoshop can be used to create these color separations, which are called CMYK. |
#4
|
||||
|
||||
Here is some more:
http://graphicdesign.spokanefalls.ed...ftonestory.htm |
#5
|
||||
|
||||
One of my first jobs '71-'74 was working in a 4-color shop where we did all the color separating and correction work manually with film and chemicals. Was an interesting job but had long unpredictable hours which didn't jibe with a 23 year old (me). It's hard finding complete info on the old processes like how the first steps of the color separations are made with red green and blue filters which are the opposites of cyan magenta and yellow onto continuous tone panchromatic film sensitive to all visible light. Then the process where those separations are are converted to the halftone dots with a "screen" that came in various dot pitches 80, 100, 150, 200 dots per inch etc. The halftone film was not very sensitive to red light so we could use red safe lights in the contact room where we'd do that. Anyway got me to reminiscing! Just as I was leaving in 1974 the company had just purchased one of the first color transparency scanners. Big machine from Germany about 6 ft wide with a spinning cylinder you'd mount the color slide or transparency to and an optical head would move across it while it was spinning is about all I remember about it. We did everything from magazine ads and product packaging to the Neiman-Marcus Christmas catalog.
Last edited by Ed in Tx; 08-25-2018 at 10:53 PM. |
Audiokarma |
#6
|
||||
|
||||
In 1974 you had film scanners?
But to what they connected the machine? |
#7
|
||||
|
||||
Quote:
Similar to this... Last edited by Ed in Tx; 08-26-2018 at 08:49 AM. |
#8
|
||||
|
||||
As Ed in Tx says, these machines were self-contained. They had a photocell to scan the original, and analog circuits to compute the correct amount of cyan, magenta, yellow, and black. This controlled four beams of light to expose four black and white transparencies for the four printing plates. They were tedious to adjust to match the properties of the inks and printing press, so they were used to standardize the process for a printing plant that did lots of work on the same materials. Hence, they were first developed in conjunction with the very largest printing plants that did national magazines like LIFE and Time. They cost something like $200,000 each.
Due to the slow process of adjusting and the cost, they could not be used by an individual photographer on an image-by-image basis. Any artistic modifications to a photograph had to be done the old fashioned way first, and then this machine would be used to get the most consistent printed reproductions. The famous photographer Ansel Adams lived long enough to see these machines, and speculated that the technology might some day allow manipulation of color photographs equivalent to what he did with black and white; but he never had personal access to a scanner, computer, spectrophotometer, and printer, all of which you can have at home today. Today we have all the devices and software that allow much quicker adjustment of the process when different paper, inks, or printing machines are used. Still, it's something of a difficult and not entirely perfect process, but much quicker and easier to measure and correct for errors. Drum scanners are still considered to be the highest quality devices for scanning transparencies today, but since most photography is digital, there is much less volume of work for them. Last edited by old_tv_nut; 08-26-2018 at 10:59 AM. |
#9
|
|||
|
|||
Quote:
He served an Apprenticeship right after high school for the trade of Litho-platemaker. Is the machine pictured known as a Mezzomax? If so, that was one part of his job, operating it. Milwaukee was a large printing town, as a result of the paper mills that were close. |
#10
|
||||
|
||||
That is an interesting question. "Mezzomax" seems obviously to be a trademark, but searching on line shows "mezzo" only as part of an old, old term, "mezzo tint," for hand-made art prints, not photographic reproductions. Furthermore, Wikipedia states that mezzo print plates were degraded slightly by each impression until they were discarded because the prints became too poor, after maybe a couple of hundred impressions.
More from searching: Mezzo tint involves a faster process than line engraving to make the ink-holding areas, by roughing the plate with a large area "rocker" tool or some kind of shavings instead of engraving one line at a time with a sharp pointed tool. The first impressions from a mezzo tint plate have deep blacks and excellent shading, but the rough plate areas that hold the ink in a mezzo tint are not as deep or durable as line engravings and get smoothed eventually by the successive high-pressure impressions. Perhaps "Mezzomax" is a brand name for a plate making machine, intending to convey the quality of mezzo tint images (?) |
Audiokarma |
#11
|
||||
|
||||
Scanners mentioned in "The Reproduction of Color (6th ed.)" by R.W.G. Hunt:
Hardy and Wurzburg (first invented in 1948) Their academic paper was realized in several forms of flat-bed hardware over a decade, by several companies including Interchemical and RCA. The first one required photographic color separations, but did the calculations for each ink color from the three color separations. Exposure was onto photographic plates. P.D.I. (Printing Developments Incorporated), also known as the Time-Life Springdale scanner, circa 1951. This one scanned a color transparency on a drum, and exposure was on photographic film. Fairchild, circa 1964 - drum scanner Other drum scanners: Crosfield; Hell; Linotype-Paul Linoscan Other flatbed: Hell Colorgraph (1958); Hell Vario Klischograph (1954, 1957), which made directly engraved metal printing plates or halftone films; Others:Hunter-Penrose; Crosfield Scanatron; Log-Etronic |
#12
|
||||
|
||||
Quote:
|
#13
|
||||
|
||||
You people there had a lot of stuff...
|
#14
|
||||
|
||||
I worked for Crosfield c1984. Not on the scanners though they were certainly around. I was working on high resolution graphics systems. 1024x1024x32 bit deep memory. All in 64kb DRAMs. Lots of 64kb DRAMs. Along with PDP11 based computers and washing machine sized hard disk drives with interchangeable disk packs. Huge and horribly expensive kit that would be obsoleted by PCs and Macs a few years later.
Crosfield did a lot of work on RGB<>CMYK conversion in the days before Adobe created de facto standards for colur representation in computer systems. And photoshop became the industry standard for image manipulation. |
#15
|
||||
|
||||
Do you mean Chicago Typewriter? They had a most memorable slogan: "Keep the change ya filthy animal".
|
Audiokarma |
|
|