TL;DR: Getting artwork into production without rework cycles depends on how your files are structured before they reach our prepress team — not after.
TL;DR: Over 60% of first-sample iterations we process trace back to three file handoff gaps: wrong colour profile, missing font outlines, and dieline/artwork layer mismatches — all preventable before the file leaves your studio.
How We Ingest Your Files: What Happens in the First 30 Minutes of Prepress #
When a new artwork file arrives, our prepress team runs it through what we call the FP-01 intake review — a structured check that takes roughly 25–30 minutes per SKU. This is not a passive file open. We’re looking at Acrobat preflight output, Illustrator layer structure, ink coverage values, and dieline registration simultaneously.
The single most time-sensitive check is colour space. Files submitted in RGB with embedded sRGB IEC61966-2.1 profiles require conversion before plating — and conversion introduces shift risk, particularly in brand colours that sit near the edge of CMYK gamut. We convert to ISO Coated v2 300% (FOGRA39) for coated offset jobs, and to FOGRA47 for uncoated work. Files submitted pre-converted to the correct ICC profile skip this step entirely and move to plate output 4–6 hours faster.
Here’s a practical snapshot of what we see at file intake and what it means for your timeline:
| File Condition at Intake | Prepress Action Required | Typical Delay Added |
|---|---|---|
| CMYK, correct ICC profile, fonts outlined | Direct to plate output | 0 hours |
| RGB, no profile embedded | Convert + soft-proof review | 4–6 hours |
| Fonts live (not outlined), no font package | Font substitution or artwork hold | 8–24 hours |
| Dieline on wrong layer / mixed with artwork | Manual separation + client confirm | 12–48 hours |
| Ink coverage >300% on coated stock | Recolour review + client approval | 8–16 hours |
A file that lands in row one goes to our CTP (computer-to-plate) queue the same shift. A file in row four doesn’t move until we’ve confirmed the recolour with you — and that approval window alone often spans one to two business days across time zones.
We output plates at 175 lpi for standard offset litho jobs and 200 lpi for fine detail work like cosmetic secondary packaging. If your artwork includes fine serif type below 6pt or reversed-out text on dark backgrounds, flag it — we’ll adjust screen angle assignments to reduce moiré risk on those elements.
What Breaks During Handoff — and Why It’s Rarely the Printer’s Fault #
The most common integration failure we see is not a print defect. It’s a file architecture problem that only becomes visible when artwork meets the physical dieline.
Bleed constructed incorrectly is the highest-frequency issue in our intake log, accounting for roughly a third of sample iterations in our Q1–Q3 2024 job tracker. The standard we specify is 3mm bleed on all cut edges for folding carton work, and 5mm on rigid box wraparound materials where the substrate can shift slightly during hot-press lamination. When a designer builds bleed at 2mm — common because some US-based templates default to 1/8 inch (approximately 3.175mm, close but not exact in metric setups) — edge print loss at the cutter shows up as a white hairline on the finished pack. At 175 lpi the eye picks this up immediately. The fix requires a new file, a new plate, and another sample cycle.
The second failure mode involves overprint settings. Black text set to overprint in Illustrator or InDesign behaves correctly on press — ink layers, preventing knockout halos. But when a designer applies overprint to a spot colour incorrectly, typically by globally enabling it without checking which objects it affects, large solid colour areas print as a muddy blend rather than opaque coverage. We catch this in our FP-01 review using Acrobat’s overprint preview, but only if the file includes a properly embedded PDF/X-4 or PDF/X-1a output intent. Files without an embedded output intent slip through this check more often, and we’ve seen the consequence surface on actual press sheets. PDF/X-4 is our preferred submission format per ISO 15930-7 precisely because it mandates output intent declaration.
The third scenario is less about prepress and more about physical integration: artwork scaled to a dieline version that has since been updated by the structural team. This happens when packaging development and brand design run on separate project tracks without a shared version-control handshake. A dieline revised to add 1.5mm to a tuck-flap depth (a common structural tweak after a physical fit test) invalidates every safe zone and bleed boundary in the artwork file. We’ve held entire sample batches on this exact issue. When briefing us, always confirm which dieline revision your artwork was built on — we assign revision codes to every dieline we issue (format: DL-[JobCode]-R1, R2 etc.) and cross-check them at intake.
Does Resolution Actually Matter for Flexo vs. Offset? #
Yes, but the threshold differs significantly between processes.
For sheet-fed offset, we require raster images at 300 dpi at final print size, referenced against ISO 12647-2 for process control. For flexo, particularly on corrugated and flexible film substrates, 250 dpi is acceptable because flexo dot gain (typically 18–25% at midtones on film) limits the practical resolution ceiling anyway. Submitting a 600 dpi TIFF to a flexo job doesn’t improve output — it increases RIP processing time and can introduce moiré from the anilox screen interaction if the image file is not pre-screened correctly.
This holds for most standard substrates. On digital inkjet for short-run work, we run at 1200 dpi natively, so files below 300 dpi will visibly degrade — especially in gradient transitions and photographic imagery.
Specification Notes for Brand Partners #
When you brief us on a new SKU, the three things that unlock an accurate quote and clean first sample are: the confirmed dieline revision code, the colour standard (Pantone reference numbers for all spot colours, or your own brand colour profile if you have one), and the intended substrate. These three inputs let us set ink sequence, screen angles, and bleed parameters correctly from day one.
The most common brief gap that causes back-and-forth is an unspecified finishing interaction. If your artwork sits under a spot UV varnish, soft-touch laminate, or foil stamp, the artwork file needs to include a separate finishing layer with those areas marked. Designers sometimes supply this as a separate PDF rather than a layer within the master file — that works, but confirm it explicitly. Unmarked finishing zones mean our prepress team has to guess, and we won’t guess on your brand asset.
Our standard sampling timeline from confirmed, compliant file to first physical sample is 10–14 working days for folding carton and 18–22 working days for rigid box formats. Files that require prepress rework (any condition below row one in our intake table) extend that timeline by the delays shown. Expedited sampling to 7 working days is available for folding carton when the file is clean at intake.
Frequently Asked Questions #
What file format should I submit for an OEM packaging project?
PDF/X-4 is our preferred format — it embeds output intent per ISO 15930-7, handles live transparency correctly, and allows our FP-01 intake review to complete without conversion steps. Native Illustrator (.ai) or InDesign (.indd) packaged files are accepted as backups, but they add prepress time.
My designer says the file is print-ready. Why did it come back with revision requests?
“Print-ready” means different things in different workflows. A file that passes a generic PDF preflight in Acrobat can still carry RGB images in embedded objects, incorrect overprint settings on spot colours, or bleed built to a dieline revision that doesn’t match our structural team’s current version. Our FP-01 intake review checks against the specific print process and substrate for your job — not a generic standard. The most common trigger for a return is ink coverage above 300% TAC on coated stock, which risks setoff during stacking even when it looks fine on screen.
Can I submit Pantone colours and expect an exact match on press?
It depends on whether you’re specifying a Pantone spot ink or expecting a CMYK simulation. A true Pantone spot ink (mixed from the Pantone Matching System using CMYK or extended gamut base inks) will match within the tolerance defined in ISO 12647-2: ΔE 2000 ≤ 2.0 for process colours and ≤ 3.0 for brand-critical spot colours, measured against an approved OK-sheet. CMYK simulation of a Pantone value on coated stock will drift more — some Pantone colours, particularly saturated oranges and violets, sit outside sRGB and FOGRA39 gamut and cannot be closely matched in four-colour process. If colour accuracy is critical for your brand, specify a spot ink and provide a physical colour standard with your brief.
How does a dieline revision affect an already-approved artwork file?
Any change to the dieline’s cut path, crease lines, or panel dimensions invalidates the artwork’s safe zones and bleed boundaries, even if the change is small. A 1.5mm extension to a tuck flap, for instance, shifts the fold crease relative to artwork elements near that edge. Our practice is to issue a revised dieline (incremented revision code) and request artwork confirmation before proceeding to plate. If your structural and brand teams are on different timelines, align on a dieline freeze date before artwork production begins — that single step eliminates most of the rework cycles we see on multi-SKU projects.
Planning a packaging project? Contact our team to request a complimentary specification review and sample quote.
