How to prepare images for printing

Every print decision flows from one question: how large will this be on paper? Fix the physical size first, then derive the pixel requirement. Working backwards from “my image is 3000 pixels” produces guesses; working forwards from “100 × 150 mm at 300 DPI” produces numbers you can check.

1. 1Decide the printed size in millimetres or inches, including whether a border is wanted.
2. 2Convert to a pixel target: size in mm ÷ 25.4 × DPI. At 300 DPI, 100 × 150 mm needs about 1181 × 1772 pixels.
3. 3Compare with what you have using DPI Checker. Shortfall means print smaller or find a better source — not upscale.
4. 4Crop to the exact printed ratio first with Crop Image, so nothing gets stretched when you set the final dimensions.
5. 5Set the dimensions with Resize Image, then save at high quality — for print, quality 90–95 or PNG is appropriate because file size is rarely the constraint.

• **Edge margin.** Most desktop printers cannot print to the very edge of the sheet. Leave 3–5 mm unless the printer is explicitly borderless.
• **Contrast.** Screens are backlit; paper is not. Images that look correct on a monitor often print lighter and flatter. A modest contrast lift helps, and Document Filter does exactly that for scans.
• **Grain and noise.** Sensor noise that is invisible on screen becomes visible as speckle in print. Reducing it before printing is far easier than reprinting.
• **Colour.** If the printer is colour-managed, work in the space it expects. When in doubt, print a test strip rather than a full page.
• **Paper choice.** Matte paper hides fingerprints and shows fine text well; glossier surfaces show saturation but reveal every flaw.

• **Several photos on one sheet** — Photo Sheet builds an automatic grid where each photo fits its cell without distortion.
• **One photo repeated at an exact size** — Photo Print Layout uses an explicit columns-by-rows grid with each copy at a precise millimetre size.
• **A photo enlarged to fill a page** — A4 Print Sheets handles 4-up, 6-up and 9-up layouts with borders and captions.
• **A whole document to print** — Document Print Prep re-paginates a PDF to your paper size and orientation without rasterising it.

Whatever tool produces the sheet, print at 100% scale — never “fit” or “shrink to fit”. Fit mode silently resizes the page and ruins measurements that were set in millimetres.

• Print a single test page — especially if the sheet will be cut or used for photo sizes.
• Check the corners: nothing important should sit where the printer cannot reach.
• Confirm the orientation of every page before committing a whole job.
• Check the result at 100% zoom on screen as well; some layout errors are obvious there before any paper is used.