Print & production
Preflight: the print checks
Preflight is the last honest look at your file before it leaves the building. Popcorn Editor runs it automatically inside the Export dialog and lists what it finds in a small Print checks panel — so you catch a soft image or a lost spot plate here, not on the proof.
What preflight is here
The Print checks panel sits near the bottom of the Export dialog, in a quiet amber block. It lists potential print problems for the export you're about to run — and that's all it does. It is informational only: it never blocks the export, never greys out the button, never nags. Its whole job is to warn you before your printer does.
The list is live. It recomputes whenever you change the Output Format, flip the color space between Print (CMYK) and Digital (RGB), or toggle Editable text — because those choices are exactly what decide whether a spot color survives or an image has to rasterize. So if a warning bothers you, changing the relevant option often clears it on the spot.
The panel only appears when there's something to say. An empty Print checks panel means every check passed for this export configuration.
Low-resolution images
image-low-res — "{count} image(s) below 300 PPI (lowest {min} PPI) — may print soft or pixelated."
This is about effective PPI, not the file's native resolution. Effective PPI = the image's source pixels divided by its printed size, so scaling a photo up on the canvas lowers its effective PPI even though the file never changed. An image that's crisp at 40 mm goes soft when you stretch it to 120 mm.
This check runs on CMYK (print) documents only — flagging it in a screen/RGB document would light up every image. Fix: swap in a larger source file, or scale the image down until it clears 300 PPI. The same warning shows as a badge on the image itself in the Properties panel, so you can hunt down the culprit on the canvas.
The spot-color checks
Most preflight messages are about keeping spot colors intact all the way to a real separation. Here's each one and how to clear it.
| Message | Why it fires | Fix |
|---|---|---|
spot-lost-format — "This format cannot preserve spot colors — {names} will be flattened to their preview values." |
The chosen target carries no Separation color space: PNG, JPEG, WebP, SVG, PPTX, or a Digital (RGB) PDF. | Export a Print (CMYK) PDF to keep the separations. |
spot-rasterized — "{count} objects using spot colors have effects, masks or gradients and will be rasterized to process CMYK: {names}." |
Effects, masks and gradients can't stay vector, so those objects convert to process CMYK and lose their spot plate. | Remove the effect/mask/gradient from that object, or accept process CMYK for it. |
spot-board-rasterized — "A background-blur effect rasterizes the whole artboard — spot colors on it become process CMYK." |
A background blur needs the backdrop, so the entire canvas is rasterized — taking every spot plate with it. | Remove the background blur if the spot plate matters. |
spot-in-rgb-doc — "Spot colors are used but the document is in RGB mode — switch to CMYK to export separations." |
The document's Color mode is RGB, where spot colors can't separate. | Switch Color mode to CMYK (print). |
spot-case-collision — "Spot names {names} differ only by case and will output as separate plates." |
Two swatches like Die Cut and die cut read as different plate names on the press. |
Rename them so the plate names match exactly. |
spot-process-colorant — "Spot name {names} matches a process ink name." |
A spot named e.g. Cyan collides with one of the four process plates. |
Rename the spot to something unambiguous. |
One message is purely informational: spot-text-outlined — "Text using spot colors always exports as vector outlines (not selectable text)." That's expected behavior, not an error. Spot-colored text is converted to vector outlines so its plate assignment survives; it just won't be selectable in the PDF.
How to act on the panel
Read the Print checks every time you export. Most items are one-move fixes — widen a gutter, swap an image, rename a swatch, switch the color space. Because the list recomputes as you change options, you get instant confirmation that a fix took. Treat a clean panel as your green light. For the deeper story behind image resolution, see the Image resolution reference; for a full pre-send routine, see the preflight checklist in the learn library.
Next
- Spot colors & print separations — how separations are built and named.
- Exporting a print-ready PDF — the export path these checks guard.