As part of the «Fundamentals of Print and Prepress» elective, our group was assigned a project: to create a personal «book of mistakes» for the future. This small booklet should compile as many examples as possible of things that should not be included in a layout before printing, and what results will occur if these issues are ignored.
However, before depicting errors, one first needed to realize where errors could possibly occur.
In addition to practical sessions, we visited two tours: one at an offset printing house and one at a digital printing house.
where we saw the RIP, densitometer, and four- and five-color printing machines.
At the offset printing shop, our group caught a fortunate moment—the machine was reprinting one of the defective test runs. Immediately afterward, we measured the optical densities for the new printing plate and prepared four new aluminum plates (one for each CMYK color). The image is transferred to the paper in layers from these plates during offset printing.
In the digital print shop, the focus was on color calibration and demonstrating the «inner workings» of the printing press.
With the help of a spectrophotometer, we created a color profile for the printing process that would comply with printing standards (matching the contractual color swatch and specified $\Delta E$ intervals).
Then they opened the printer’s shutter to show the toner tubes.
It turns out that establishing a profile for gray shades is particularly difficult because they exhibit strong metamerism in digital printing.
For a few moments, we were allowed to view the photosensitive film and the drums, where a layer-by-layer, frame-by-frame image ready to be transferred onto paper is created through potential differences.
With accumulated experience, it was possible to begin creating an «errors book.»
Tasks and examples of errors were provided. But I checked a few things in the booklet additionally.
For example, I asked to disable color management for the 400% black cover to see how the excess toner would crack and flake.
Or she put tiny text right at the edge of the sheet: «Cut me if you can» (they could).
The greatest attention was given to color, its manipulation, and its correction, both in black-and-white and in color.
The brochure includes various color separation strategies: trapping, reverse trapping, and overprinting.
Color gamut and screen color proofing were a small discovery for me. It was interesting to search for colors that are difficult to print and try to correct them.
The ultramarine on the left of the image was compressed into violet tones, and the background texture was lost.
However, the most revealing mistakes were those made unintentionally.
Inaccurately laid-out spreads
images that folded inside
Text cropped due to crooked folding
Unnoticed dangling prepositions, hyphenation errors, typos
