File preparation guide
Image resolution for print: how many dpi do you really need?
Resolution is how many image dots fit into each inch of paper, at the size the image is actually printed. The same image can be sharp at stamp size and blurry at poster size — the dots are stretched over a larger area.
The rule for things held in the hand
Flyers, business cards, booklets, menus: about 300 dpi at the printed size. Below 200 you start to see soft edges on letters and faces; below 150 the image looks pixelated even from a distance.
Signs and roll-ups: viewing distance matters
A sign read from two meters away does not need 300 dpi. For a roll-up or a large sign, 100–150 dpi at full size is usually enough; for a billboard seen from the road, even less. The print shop can set its own threshold per product.
How to work it out without software
Divide the image width in pixels by the printed width in inches. An image 1800 pixels wide printed 6 in wide gives 300 dpi — excellent. The same image printed 24 in wide gives 75 dpi — too weak for anything held close.
What does not help
Enlarging an image in software adds no detail — it only makes the file bigger. Changing the dpi number without changing the pixels changes nothing. What helps: the original file from the camera or photographer, a new photo, or using the image smaller in the design. Screenshots and social media images are usually small and compressed.
What Drapress checks when the file is uploaded
Drapress works out, for every image in the file, the resolution at the size it is actually printed, and flags an image below 150 dpi with a target of 300 — for a poster, roll-up or banner, a lower line that fits how far away it is seen — or the threshold the print shop set for the product. The weak image is marked on the page, so you see exactly which one it is.
See it in action
In this video (75 seconds, no sound) a sample file goes through the Drapress check, from upload to sending it to the print shop.
Read the video as text
The file looked fine on screen. At the press, the bleed falls short. And a photo that may print blurry. Upload your PDF. Your original is kept. Live view of every check: size, bleed, fonts, colors, images. Bleed missing on page 3: a thin white strip may show after trim. Step by step: the photo on page 5? Replace it, or accept it as it is. Screen colors (RGB): the shop converts them for print; shades may shift. Missing bleed? A few clicks build it from the page's own edge. It fixes only what is safe to fix. Before and after: the background now runs past the cut line. A warning left? You decide, then send it to the print shop.
What an automatic check cannot catch
The check measures pixels, not quality: a high-resolution photo that is out of focus, or one already compressed until detail was lost, passes. Look at the proof zoomed in.
