Is My Artwork Print Ready? A Pre-Flight Checklist

Why Pre-Flight Matters

You're about to burn screens, mix inks, or queue up a DTF gang sheet. The last thing you want is to discover the file is 72 DPI, has seventeen gradients, or needs an underbase you didn't plan for. Pre-flighting—checking a file before production—catches those problems while you can still fix them or send the file back to the customer.

A solid pre-flight routine protects your press time, your ink inventory, and your reputation. It's the difference between a smooth run and a scramble for remakes. This checklist walks through the critical checks every shop should make, whether you're printing plastisol on darks or running full-color DTF transfers.

If you want software to automate most of these checks, AI Separations includes a Print Doctor that flags resolution, color count, banding, fine detail loss, and whether the design needs an underbase or is better suited for DTF. But even if you're checking manually, the steps below will keep bad files off your press.

Resolution: 300 DPI at Print Size

The golden rule: 300 dots per inch at final print size. Not at the size the customer sent. Not after you scale it up. At the exact dimensions it will print on the shirt or transfer.

Open the file in any image editor and check the physical width and height. A 10-inch-wide chest print must be 3,000 pixels wide at 300 DPI. If it's 1,200 pixels wide, you're sitting at 120 DPI, and the print will show pixelation, jagged edges, or soft halftone dots.

Vector art (AI, EPS, PDF with vector layers) scales infinitely, so resolution isn't a concern—just make sure you're rasterizing it at 300 DPI when you output films or separations. Raster files (PNG, JPG, PSD) are locked to their pixel dimensions. If the file is too small, ask the customer for a larger version or redraw the art as vector.

Color Count and Separation Strategy

How many colors are actually in the design? Not how many the customer thinks are in it—how many unique ink hits will you need to reproduce it faithfully?

A logo with three flat Pantone colors is straightforward: three screens, spot-color separations, done. A photo-realistic image or gradient-heavy design requires simulated process: typically four to seven halftone screens (often CMYK plus white underbase and highlight white) to blend the tones optically on press.

Count every element: underbase, each color layer, highlight white, any flash layers. More screens mean more setup time, more registration headaches, and higher costs. If the design has twelve colors and the customer's budget is for four, you have a conversation to have—or you need to simplify the art.

AI Separations' Profit Mode helps here: it can re-separate a design for fewest screens (lower cost), fastest (minimal flash), cheapest (inks you already stock), or best quality (maximum detail). That flexibility lets you match the separation strategy to the job's budget and turnaround.

Underbase and Highlight White Needs

If you're printing on dark or colored garments, you almost always need a white underbase to keep colors bright and opaque. Without it, your reds turn maroon, your yellows go mustard, and your bright blues look muddy.

Check the design: does it have light or vibrant colors? Is the substrate black, navy, or red? Then plan for an underbase. The underbase typically prints first, flashes to tack, then the color layers go on top. You may choke (shrink) the underbase slightly to avoid a white halo around edges, or trap (overlap) the colors into the white to prevent registration gaps.

Highlight white is a separate concern: a final white screen printed on top of the design to add brightness, texture, or a vintage look. It's optional and stylistic, but if the design calls for crisp white details or a pop on dark ink, plan for it in your screen count and print order.

Forgetting the underbase is one of the most common pre-flight mistakes. If your print-readiness check doesn't flag it, add a manual step: dark shirt + bright colors = underbase required.

File Format and Layer Integrity

Flattened JPGs are fine for simple raster art, but they hide a lot of problems. Compression artifacts, embedded color profiles, and baked-in backgrounds all become your problem at separation time.

Prefer layered files when you can get them: PSD, AI, or PDF with editable layers. Layers let you isolate elements, adjust colors, remove backgrounds, and proof each separation independently. If you receive a PNG with transparency, great—check that the transparency is clean and not feathered into semi-transparent pixels that will halftone poorly.

Watch for embedded fonts that aren't outlined. If the file has live text and you don't have the font installed, it will substitute, and your spacing or weight will shift. Always ask for outlined/expanded text, or convert it yourself before separation.

Color mode matters too: CMYK files are already thinking in print terms, but RGB files are common from customers. You'll need to convert RGB to CMYK (or custom ink colors) during separation. Be aware that some bright RGB colors (neon greens, electric blues) can't be matched in CMYK plastisol—manage expectations early or suggest spot inks.

Fine Detail, Gradients, and Halftone LPI

Tiny text, thin lines, and intricate details don't always survive the screen-printing process. If a design has 6-point serif type or a detailed illustration with hundreds of fine lines, you need to assess whether your mesh count, halftone LPI, and ink viscosity can hold the detail.

As a rule of thumb, text smaller than 8–10 points risks filling in or breaking apart, especially on textured fabrics like fleece. Fine lines under 1 point may not print cleanly. Either scale the detail up, simplify the art, or switch to DTF, which handles fine detail better than plastisol on fabric.

Gradients are another pre-flight red flag. Smooth gradients require high-LPI halftones (55–65 lines per inch) and precise dot gain control. Low-resolution files or coarse halftones will show banding—visible steps instead of smooth transitions. If the gradient is critical to the design, make sure your file resolution supports it and your mesh count (usually 230 or higher) can hold the dots.

AI Separations' Print Doctor flags gradients at risk of banding, fine details likely to break up, and designs better suited for DTF versus screen. That automatic triage saves you from discovering the problem mid-press run.

Screen vs DTF: Choosing the Right Process

Not every design belongs on a screen press. High color counts, photographic detail, single-piece orders, and designs with fine gradients or tiny text are often better candidates for direct-to-film (DTF) transfers.

DTF prints full color in one pass, handles detail down to small point sizes, and doesn't require screens or setup per color. The trade-off: DTF has a different hand feel (the transfer film and adhesive powder sit on top of the fabric), slightly less breathability, and per-piece costs that don't drop much with volume. Screen printing scales beautifully for dozens or hundreds of identical pieces, but setup costs make it expensive for one-offs.

During pre-flight, ask: How many pieces? How many colors? How fine is the detail? If it's 200 black tees with a three-color logo, screen print it. If it's 10 white hoodies with a full-color photo, DTF is probably faster and cheaper. If the customer insists on screen and the art has twelve colors, either simplify or be ready for a premium price to cover setup and press time.

Frequently asked questions

What resolution does my artwork need to be print ready?

300 DPI at the final print size. A 10-inch-wide design must be 3,000 pixels wide. Vector files (AI, EPS, PDF) scale infinitely and should be rasterized at 300 DPI when you output separations.

How do I know if my design needs an underbase?

If you're printing light or vibrant colors on dark or colored garments, you need a white underbase to keep the colors opaque and bright. Without it, colors will look dull or muddy.

What file format is best for screen printing artwork?

Layered vector files (AI, EPS, PDF) are ideal. Layered raster files (PSD) work well too. Flattened JPGs are acceptable for simple designs but hide compression artifacts and make separation harder.

How many colors can I print in one design?

Technically unlimited, but every color is a separate screen, setup, and registration challenge. Spot-color designs typically use 1–4 colors; simulated process uses 4–7. More colors mean higher cost and longer press time.

When should I use DTF instead of screen printing?

Use DTF for low quantities (under 24 pieces), high color counts (8+ colors), photographic detail, fine text, or complex gradients. Screen printing scales better for volume and has a softer hand, but DTF handles detail and setup faster.