Update: I have been reading about financial troubles at Landa. The company has asked for protection from its creditors in an event similar to Chapter 11 bankruptcy in the U.S. With over $500 million in debt, the company hopes to get court approval to reorganize their debt, or find other relief from their financial troubles. I will investigate and write about this in greater detail when I can.
Meanwhile… back to my analyses of the printing produced by this extraordinary machine:
Reproducing high-resolution line art
On the RGB sheet I had run on the Landa press I put a row of scans from copper engravings made in the late 19th century. These illustrations can be very challenging to reproduce.
It is uncommon in the world of graphic arts that we concern ourselves with the reproduction of scanned line art at very high resolutions. Line art illustrations were more common in the awkward era before the digital revolution of PostScript and high-resolution imaging (pre-1984). With analog graphic arts photography, the process was easier because the only limiting factor for resolution was the grain of litho film, which was effectively infinite compared to the rigid limitations that digital technologies place upon the same processes.
Defining line art
Before the invention of the photographic halftone process (credited to Frederic Ives in 1882), non-typographic illustrations – drawings mostly – were limited to inked and non-inked areas.
To reproduce “tonal” photos on printing presses, the most common type of illustration was the line engraving. These were typically made by artisans who engraved drawings into copper or steel plates (in earlier eras, they used hardwood). Using techniques including the control of line thickness, cross-hatching, and line shapes to create the illusion of tonality in an image, these craftspeople made extraordinarily nice illustrations in metal using hand engraving tools. To see a perfect example of this technique, examine any printed currency, which is still created by the hand engraving process.
The primary printing process for currency is sheet-fed intaglio, which is how this image was made. U.S. currency also has elements printed by offset lithography and letterpress.
If you look at a photomicrograph of the U.S. $5 note, you’ll see all of these techniques at play. Notice the circular lines around the corneas, the sculpted lines that run over Lincoln’s nose, and back down, and the crosshatching of the lines across his forehead. These are the techniques of a master engraver. There is only one color of ink used to print this illustration: black. It is the interaction of these clever engraving techniques with the paper that creates the illusion of tonality where there is none.
And it is those same lines and crosshatches that are so difficult to reproduce on many printing machines – including the Landa press. Electrophotographic machines (toner) also suffer with images of this type. Offset and non-roto intaglio certainly can reproduce images in this class. But, rotogravure is fatal to line images like this because the process converts everything into halftone-like patterns. A common example of this is text printed in the Sunday New York Times Magazine, which is printed by rotogravure.
It is ultimately the resolution of the machine itself that prevents this kind of illustration from being reproduced in a way that rivals offset lithography. The Landa presses use Fuji Dimatix ink-jet heads to make their marks on the paper (and other non-paper substrates). The resolution (addressability) of those ink-jet heads is 600 machine spots per linear inch. Fortunately for the Landa press, the machine spots created by the ink-jet heads are stunningly sharp, and their sharpness is not degraded as the ink is transferred to the substrate from the imaging belt (a continuous ribbon of plastic material that catches the ink from the nozzles, then, after being dried, transfers that ink with pressure to the substrate). See the press diagram below.
Now let’s compare that resolution to that of an aluminum printing plate on a sheet-fed offset press. The image of Mr. Luse, above, was printed on a Heidelberg CD74 offset press using Kodak plates. The imaging of the plate was done on a Kodak Trendsetter laser platesetter with its resolution set to 2,400 machine spots per linear inch – four times greater than the Landa press.
For printing photos and other tonal graphics, the Landa presses produce images that are comparable to – and often better than – offset printing. But high-resolution line work seems to be the Achilles heel of the machine’s capabilities. Fortunately this does not hamper the press in the more typical processes, as scanned line art is seldom part of the modern graphic designer’s tools. These line art images are the only part of my test sheets that I would put in the fail category. The press just doesn’t have enough resolution to be effective at this.
Yet it still works!
Microscopic analysis of the reproduction of line art on the Landa press shows some curious results. Two of the images I created are surprisingly good; the rest are not acceptable. And, I suspect that only the most discerning eye would see the difference between the reproduction of scanned line art as a “halftone” or as a bitmap in the two cases where I have had success. Since the Landa press does not draw actual halftone dots, the stochastic patterns created by the Fiery front end render the two successful images acceptably.
Thus, the fault is not so much in the ability of the press to print such extraordinary detail, but the file type I selected to reproduce the scanned images. Where I had success with images scanned at 2,400 ppi for an offset press and reproduced as bitmap images, the same files don’t print successfully on the Landa when saved as .bmp (bitmap) files. Saving the very-high resolution scan as a grayscale .psd file results in a perfectly acceptable reproduction on the Landa.
And, interestingly, the Landa uses multiple colors to render these images – not just black – which enhances their appearance somewhat.
I will score this as a success on the Landa S10P press (when files are saved in the correct file format). Advice: don’t use the .bmp file format for images to print on the Landa press. Instead, save such files as grayscale and save in Photoshop .psd format.
My next tests will be published in a couple of weeks. I’m going kayaking!
