Preparing files
for print

Web files and print files are different files

Sending the image from your product page straight to a printer almost always fails. The two are measured in different units to begin with.

For the web, the pixel count is everything. An 860px image is 860px on any screen. For print, the physical size in mm comes first, and the pixel count follows from how densely you want to fill that size. So a print file starts by deciding how many millimetres across it is.

Even when the same artwork is used for both, make separate files. Trying to serve both with one usually produces a file that suits neither.

Working out pixels at 300dpi

300dpi is the standard resolution for print: 300 dots across every inch (25.4mm). So the pixel count you need works out as:

pixels across = mm across ÷ 25.4 × 300

It helps to have the common sizes worked out in advance.

Here the point from the previous article comes back — the dpi that meant nothing on the web decides the physical size in print. Print a 1181px image at 300dpi and it is 100mm; print the same file at 150dpi and it is 200mm. The pixels are unchanged, but the dots are spread thinner, so it comes out bigger and softer.

Bleed and safe margins

Printing means printing large and then cutting with a blade, and that blade does not land in exactly the same place every time. The paper shifts slightly, so there is a difference of about a millimetre on each run.

Two allowances handle it.

• Bleed — extend the background past the trim line. If the blade lands inside, no white edge appears. Usually 1–3mm on all sides, but printers ask for different amounts, so check first.
• Safe margin — keep clear of the trim line on the inside. Text and anything important goes within that line, so nothing is lost if the blade lands outside. 2–3mm is typical.

In short: let the background overflow generously, and keep the text generously inside. It is tempting to think bleed is unnecessary on a white background, but paper is not always perfectly white, so it is safer to follow the printer's guidance.

Screen color and print color cannot match

Screens make color by adding light (RGB); print makes it by layering ink (CMYK). The methods are opposites, so the range of colors they can express differs too.

These shift most visibly.

• Fluorescents and vivid primaries — the pink or green that glowed on screen comes out muted. Ink cannot reach that brightness.
• Deep blues and purples — blue commonly drifts toward purple.
• Pale blues and light greys — subtle differences that were distinct on screen collapse into one color in print.

There are two responses. When color matters, order a small sample from the printer first. If there is no time for that, avoid fluorescents and extremely vivid colors from the start and design with colors that survive printing.

Either way, put "colors may differ depending on your monitor" on the product page. That is not an excuse; it is a physical limit you cannot design around.

Black needs its own attention

Print can make black two ways, and they are used differently.

The common accident is setting small text in rich black. When the inks shift a fraction, a colored fringe appears around the letters and they look blurred. Conversely, filling a large background with K alone comes out lighter than expected.

Acrylic adds a white layer and a cut line

Acrylic is transparent. Laying color directly onto it lets the background show through and muddies it, so white ink goes down first. This is called the white layer.

Where the white goes depends on the artwork. Covering everything makes colors crisp but removes the sense of transparency; covering only parts makes those parts solid while the rest stays see-through. Areas like glass or water are sometimes left deliberately bare.

Then there is the cut line, which tells the machine what shape to cut the acrylic into. It is usually drawn with a little clearance around the artwork, and for a stand it also defines the slot for the base, or for a keyring the position and size of the hole.

The white layer and the cut line must be supplied as separate layers from the artwork being printed. Flatten them into one image and the cut line gets printed as artwork. Layer naming rules and how to specify the cut line differ between printers, so ask before ordering.

Flatten the type before sending

The fonts on your computer are not on the printer's. Hand over editable text and it reflows into a different typeface when opened there, pushing lines around and overflowing.

So type is flattened into pixels for print. Editing software calls it "create outlines" or "rasterize". makeinfo's PNG, PDF and PSD exports all have the type already flattened, so this problem does not arise.

The catch is that once it is flattened you cannot fix a typo. Always keep the pre-flattened file. In makeinfo, the full PNG (or the zip when there are many photos) plays that role.

Where makeinfo stops and the printer starts

To be straightforward about it: makeinfo runs in a browser and works in screen color (RGB). It does not do CMYK conversion, spot colors, or white layer separation.

For simple printed matter like banners or postcards, many printers accept a file exported at 300dpi size as is. For layered goods like acrylic, it is safer to get the printer's template and finish there.

Before you send

• Does the pixel count match the physical size? For a 100mm piece, check the file is around 1181px.
• Is there bleed? Confirm the background runs past the trim line.
• Is the text inside the safe margin? Move anything sitting tight to the edge inward.
• Is any small text in rich black?
• Does this order need layers? For acrylic, check the white layer and cut line are prepared separately.
• Did you keep an editable original? With only the flattened file left, one typo means starting over.
• Did you re-read the printer's guidance? Bleed values, file formats and layer naming rules vary by supplier. The numbers in this article are general references; the final authority is the printer you are ordering from.