Layout & Pre-press
Key question
When does an image appear sharp in print?
On screen, almost every image looks sharp. In print, the effective resolution is what counts: how many pixels per inch are available once the image is placed at its final size?
Learning objective: You can calculate effective resolution, choose suitable file formats, and link images correctly.
The final size determines the resolution.
4.1 / Pixels and Vectors
Pixels have limits, vectors do not.
Photos consist of pixels. Logos, icons, and graphics are created as vectors: they consist of paths and remain sharp at any size.
01
Photo
300 ppi at final size, TIFF or high-quality JPG.
02
Vector
AI, EPS, PDF or SVG: logos and graphics remain sharp.
03
Large format
Fewer DPI, as it is viewed from a distance.
Sharpness is relative to the distance.
4.2 / Effective resolution
Zooming in halves the resolution.
The effective resolution is determined by the pixel count and the placement size. If an image is enlarged to 200% in the layout, the effective resolution is halved.
In the layout program, the links panel displays the effective resolution of each image. Check it before you export, not afterwards.
Pixels divided by inches gives ppi.
4.3 / Links and formats
Linked, not embedded.
Images are linked within the layout, not copied. This keeps the layout file lean and ensures any changes made to the image are updated automatically. Missing or outdated links are a common cause of printing errors.
RGB images are deliberately converted to CMYK using the print shop's profile. Screenshots and web images do not belong in print data.
No missing links.
Exercise
Make images print-ready
Task: Prepare the images for the programme.
STEP 1
Checks the effective resolution of all images using the calculator.
STEP 2
Replaces images that are too small or resizes them.
STEP 3
Converts RGB images using the correct profile.
STEP 4
Checks all links.
Evaluation: Which images had to be replaced, and what lessons do you take from this for future briefings?