Monday, October 20, 2008
How books are printed: From Letterpress to Print-On-Demand
By Steve Glines
* Steve Glines is the book designer for the Ibbetson Street Press of Somerville, Mass.
When I was about ten my grandfather gave me a book he had been saving just for me. It was my first book. I don’t remember the title or content but it was a beautiful book, my own book. It had a dust jacket that my grandfather removed and tossed aside to reveal a soft brown leather book with the title and author embossed in 18 carrot gold on the cover and spine. Both the cover and spine had been tooled with a beautiful border. I thought the spine especially beautiful. The hide had been glued to a form of cardboard made of cotton fibers and the endpapers of the book itself were glued to the spine with the glue joint covered over with a beautiful hand made gold and green marbled paper. The body of the book had been printed by letterpress in giant 16 page signatures then sewn into a cloth backing with a Smyth Sewing machine. The first signature of the book, only 4 pages, had been printed by engraving and contained the title page with a florid design together with a portrait of the author reminiscent of those found on currency. There was a phantom signature of tissue paper between each of the engraved pages to protect the engravings.
You could tell the book had not been opened and read because the signatures had not been cut. The binding process included folding and gathering the signatures then sewing them into the backing but the resulting signatures were not trimmed as they are today. My grandfather ceremoniously handed me his paper cutter and instructed me to cut the signatures firmly but gently. For him learning how to properly open a book was a sacred right of passage. As I slowly sliced the first signature open I could feel the individual cotton fibers stretch then break as I drew the dull knife upwards. By the time I had cut the last signature the book had become mine. I would be the first person to set eyes on the printed page since they had come off the press. There was magic in that.
When I opened the book and looked at the first page in the first signature I could see the slightly uneven imprint of the type in the soft textured paper. Even without a magnifying glass I could see the needle edge of the types serifs where it cut into the paper carrying with it the carbon black filled ink. It was beautiful.
Books were made this way for several hundred years. Typesetting was a tedious, expensive and challenging work when done by hand and dangerous when done by a linotype machine that cast individual lines or slugs of metal type from negatively shaped type masters and hot molten lead. These slugs were then printed for proofing on small presses called galley presses. When all was well the slugs were then placed in a large 2 x 4 page panel for printing. Two of these were required to print one sixteen page signature. It was a slow tedious labor intensive process.
Before about 1970 fine, hardbound books were only printed by letterpress. I am old enough to remember when the change occurred. Offset printing was considered cheep and not worthy of a fine printed book. By 1980 all hardbound books were printed by offset lithography.
Offset lithography printing uses a flat metal or plastic sheet called a plate that has been photographically prepared so that ink sticks to the image area and is rejected elsewhere. Ink is transferred from the plate to a roller that presses into ink into the paper. One of the drawbacks to offset lithography is that the offset plate cannot carry as much ink to the paper or press as hard as a letterpress. Because of this the paper used in offset printing must be very flat and without the “tooth” that characterizes the “fine” papers used in letterpress. When the thin film of ink on an offset roller is pressed against the very flat paper, fine lines, dots and type serifs tend to spread so serif type faces printed by offset tend to look a little muddy when compared to identical type printed by letterpress. This feature of offset printing lead directly to an explosion in the use of san-serif type faces like Helvetica, Universe and others in book design. One good feature of offset printing is the ability to print photographs with a resolution many times greater than letterpress offers.
In older books photographs were often printed individually then glued or “tipped” into the book or entire signatures of photographs or drawings were printed by etching presses then sewn into the book. The maximum resolution of a letterpress was about 45 dots per inch using newsprint and as much as 85 dots per inch using paper specially prepared for the purpose. This paper was often hard and brittle from the clay used to prepare the paper to take a very sharp image. The harder and flatter the surface the sharper the dots could be. Etching presses or rotogravure, are capable of impressions of up to 200 dots per inch but this process is very expensive and gravure doesn’t print type very well at all. The colorful magazines distributed with Sunday Newspapers were always printed by rotogravure. That was then; today both newspapers and the colorful magazines they contain on Sunday are printed by offset. Because offset printing was an inexpensive way to print both type and art on the same page it became very popular with textbook publishers. It didn’t take long for paperback publishers to switch to offset followed quickly by traditional publishers.
Not only did the switch to offset represent a revolution in printing at the same time there was a revolution in typesetting. Letterpress printing was a part the old industrial revolution characterized by big dirty machines, steam engine technology. Typesetting was a blue-collar profession conducted in the bowls of a factory. Type was literally hot as the liquid lead flowed down open channels to form the slug in a linotype machine. In the late 1960’s “cold type” became popular. Early “cold type” systems came from IBM Selectric ™ Typewriters modified to print real typographers’ fonts onto specially prepared paper and Compugraphic ™ and other brands of machines that composed type onto photographic paper. These galleys would then be used to “paste-up” a dummy of the publication which then was then used to photographically create an offset plate.
Today, of course, hot type and paste-up is a thing of the past because of the multitude of personal computer programs that can electronically paste-up, proof the image on ink jet or laser printers and electronically create an offset plate. Xerox, Hewlett Packard and Kodak all pioneered in the use of ink jet and laser as “page-proof printers” with a quality image that rivaled or bettered that produced by an offset press.
The best offset printers can print images with a resolution of 300 dots per inch at a rate measuring in the thousands of impressions per minute but an offset pressman might have to print as many as 50 sheets to get the inking on a plate exactly right before turning up the press. Because of the tuning required an offset job is cheaper than a proofing press only of the print run exceeds many hundred or thousands of impressions. For many years book publishing has been constrained by the economies of scale in offset printing. For example, printing a 200 page paperback book might cost as much as $2000 to set up and 2 cents per impression. Printing and binding 100 copies could cost $35 or more per book but in quantities of 50,000 the cost falls into the range of pennies per book.
Modern proofing presses, for example Hewlett Packard’s Indigo series of industrial laser printers, are capable of printing an 11” by 17” images in full color with a resolution of 1200 dots per inch at the rate of up to 1000 pages per minute. The quality of the image produced by these printers is superior to almost all offset printing but cost considerably more than offset at its optimum but considerably less than offset in very small quantities. With the introduction of home, commercial and industrial laser printers “printing on demand” was born and “publishing on demand” soon after.
Publishers face two dilemmas: First, Can they sell enough books to make publishing worthwhile? Second, how can publishers keep their back list alive without having to print and stock uneconomical quantities of books? For most mainstream publishers pre- and post-publication costs dictate an initial print run of many thousands of books. These same economics prohibit the publication of books with potentially smaller audiances and prohibit altogether books on the backlist that could have long but active tails. A book by a major publisher that might sell 100 – 300 books a year in perpetuity is quickly marked out of print.
“Publishing on demand,” or POD, is a technology that solves the problem of small press runs. POD marries laser proofing technology with conventional bindery equipment to create a book production system that is as efficient at printing a one-of book as it is 2,000 books. Of course the unit cost is much, much higher and the production rate much lower than offset but back listed books that once would have gone out of print can be quickly and effectively produced by a Lulu or Lightning press one at a time at a cost point guaranteed to earn the publisher a profit.
To a small to medium sized publisher POD is a revolution. Not only does the use of POD eliminate an investment in inventory but the quality of publication is greater or equal to that produced by offset. The simple elimination of large inventories allows smaller publishers to publish more books than they otherwise could and the availability of POD published works guarantees that no book will ever go out of print. The agility of POD will almost guarantee that new and exciting works will flow to those publishers who using POD, will be able to respond quickly and decisively to the market. By reducing the cost to market while maintaining expected quality will insure the publisher using POD will have an advantage over their more conventional competition.