DIS Print Production & Prepress 1 — Questions and Answers
Question 1: In prepress production, what is the primary purpose of 'trapping'?
- To prevent white gaps at color boundaries caused by misregistration on press (Correct answer)
- To increase ink density for more vibrant color output
- To separate colors into individual channels for plate making
- To reduce file size for faster RIP processing
Correct answer: To prevent white gaps at color boundaries caused by misregistration on press
Trapping adds slight overlaps between adjacent colors so that minor press misregistration does not create visible white gaps between color areas.
Question 2: What does a Raster Image Processor (RIP) do in a print production workflow?
- Converts vector and image data into raster dot patterns for output devices (Correct answer)
- Compresses image files to reduce storage and transfer requirements
- Automatically calibrates printer ICC color profiles
- Manages network file transfers between prepress workstations
Correct answer: Converts vector and image data into raster dot patterns for output devices
A RIP interprets page description languages (PostScript, PDF) and converts all content into the raster dot patterns that imagesetters, platesetters, and digital presses can reproduce.
Question 3: In offset lithography, what is 'dot gain'?
- The spreading of ink dots on the substrate that makes halftone dots appear larger than designed (Correct answer)
- A technique for increasing apparent image resolution during RIPping
- A method to enhance shadow detail in highlight-to-shadow gradients
- The increase in digital file size caused by embedding color profiles
Correct answer: The spreading of ink dots on the substrate that makes halftone dots appear larger than designed
Dot gain occurs when ink spreads as it transfers from plate to blanket to paper, causing halftone dots to physically enlarge and making prints appear darker than intended.
Question 4: What is the typical total ink limit (TIL) for coated paper in CMYK offset printing?
- 320–340% (Correct answer)
- 100–120%
- 400%
- 200–220%
Correct answer: 320–340%
Coated stock can accept roughly 320–340% total ink coverage; exceeding this risks slow drying, setoff, and paper damage even though four channels theoretically allow 400%.
Question 5: What is 'overprinting' in prepress, as opposed to a knockout?
- Printing one ink layer directly on top of another without removing the underlying color (Correct answer)
- Exceeding the maximum recommended ink density for a given substrate
- Adding extra bleed beyond the standard specification to a print file
- Using more than four color separations in a single print job
Correct answer: Printing one ink layer directly on top of another without removing the underlying color
Overprinting allows an ink (commonly black text) to print over a background color rather than cutting a white hole (knockout), preventing gaps if registration shifts slightly.
Question 6: What is the standard bleed dimension used in US commercial print production?
- 0.125 inches (1/8 inch) beyond the trim edge (Correct answer)
- 0.5 inches (1/2 inch) beyond the trim edge
- 0.0625 inches (1/16 inch) beyond the trim edge
- 0.25 inches (1/4 inch) beyond the trim edge
Correct answer: 0.125 inches (1/8 inch) beyond the trim edge
US commercial printing uses a 0.125-inch (1/8-inch) bleed so that background colors and images extend past the trim line, preventing white slivers after cutting.
Question 7: Which file format is the industry standard for delivering print-ready files to a commercial printer?
- PDF/X (Correct answer)
- JPEG
- PSD
- EPS
Correct answer: PDF/X
PDF/X is an ISO-standardized subset of PDF created specifically for reliable prepress exchange, enforcing embedded fonts, appropriate color spaces, and no missing elements.
DIS Print Production & Prepress 1
In prepress production, what is the primary purpose of 'trapping'?