GMI Performance Optimization 3 — Questions and Answers
Question 1: To optimize a multi-page publication for offset printing, which PDF compression method preserves sharp edges on text and line art?
- JPEG compression for all objects
- ZIP compression for line art and JPEG for continuous-tone images (Correct answer)
- CCITT Group 4 for all objects
- Run-length encoding for all content
Correct answer: ZIP compression for line art and JPEG for continuous-tone images
ZIP compression is lossless and ideal for sharp-edged line art, while JPEG efficiently compresses continuous-tone photographic content.
Question 2: When batch-processing color corrections across hundreds of images, which approach minimizes processing time while maintaining consistency?
- Apply corrections manually to each image
- Use a Photoshop action with a calibrated adjustment layer (Correct answer)
- Convert all images to grayscale before correcting
- Process each image through a separate ICC profile conversion
Correct answer: Use a Photoshop action with a calibrated adjustment layer
A Photoshop action with calibrated adjustment layers automates consistent corrections across all images in a single batch operation.
Question 3: In graphic reproduction, what does 'GCR' (Gray Component Replacement) primarily optimize?
- Gamut range for RGB displays
- Ink consumption and drying time in print (Correct answer)
- Screen angle for halftone rosettes
- PDF file compression ratio
Correct answer: Ink consumption and drying time in print
GCR replaces CMY gray components with black ink, reducing total ink coverage and improving drying performance on press.
Question 4: A workflow uses JDF (Job Definition Format) to automate press-to-prepress communication. The primary performance benefit is:
- Higher color accuracy in proofs
- Elimination of manual data re-entry between systems (Correct answer)
- Better halftone screening
- Faster PDF rendering
Correct answer: Elimination of manual data re-entry between systems
JDF automates job information exchange between systems, eliminating manual re-entry and reducing workflow bottlenecks.
Question 5: Which technique best reduces moiré patterns when scanning previously printed halftone artwork, improving output quality?
- Increasing scan resolution to 1200 PPI
- Using a descreen filter set to the original halftone frequency (Correct answer)
- Converting the scan to CMYK immediately after capture
- Scanning at 45 degrees to the halftone grid
Correct answer: Using a descreen filter set to the original halftone frequency
A descreen filter specifically targets and removes the halftone dot pattern at the frequency it was originally printed, minimizing moiré artifacts.
Question 6: For a digital press workflow, what is the most effective way to handle variable data printing (VDP) without creating excessively large print files?
- Rasterize all variable elements before sending
- Use PPML or PDF/VT with reusable object streams (Correct answer)
- Create a separate PDF file for each recipient
- Embed all fonts as outlines in each record
Correct answer: Use PPML or PDF/VT with reusable object streams
PPML and PDF/VT store fixed graphic elements once as reusable objects, dramatically reducing file size and RIP processing time for VDP jobs.
Question 7: Which color rendering intent should be selected when converting photographic images to a smaller-gamut CMYK profile to preserve overall tonal relationships?
- Absolute Colorimetric
- Relative Colorimetric
- Perceptual (Correct answer)
- Saturation
Correct answer: Perceptual
Perceptual rendering intent compresses the entire source gamut to fit the destination, maintaining tonal relationships even when colors must be remapped.
GMI Performance Optimization 3
To optimize a multi-page publication for offset printing, which PDF compression method preserves sharp edges on text and line art?