Tips for the best separations

How to get press-ready seps out of Separation Engine, from art prep to the press check.

1. Start with good art

• Resolution is everything. Aim for about 300 DPI at the size you will print. A 12" wide print wants art around 3600 pixels wide. Soft, low-res art gives jaggy edges and muddy halftones no matter how good the seps are.
• Upscale before you separate, not after. Pick the print width (4" left chest, 10", 12", 14"), then Upscale. AI rebuilds edge detail; Smooth is an instant clean resize. Upscaling re-runs the seps on the new art.
• Use PNG when you can. JPG compression leaves blocky noise around edges that turns into specks on film. A transparent PNG with the background already removed is the cleanest start.
• Flatten effects in your art program. Drop shadows, glows and textures are fine, but they should be baked into the image you upload.
• Art Adjust (saturation, vibrance, brightness, contrast) is a quick fix for flat or dark art. After adjusting, tap a color count preset to re-pull inks from the adjusted art.

2. Set the shirt color first

• Pick the real garment color. Use the shirt sampler on the art if the background is the shirt, or set it by hand. Wherever the shirt is the closest match to the art, nothing prints and the shirt shows through.
• Let the shirt be a color. Navy art on a navy shirt doesn't need a navy screen. When you change the shirt color, Auto re-picks the inks and drops any the shirt already covers.
• No shirt is for transparent art that's already cut out. It separates the art itself with nothing knocked out.
• Dark shirts get an underbase automatically (Underbase: Auto). Light shirts don't need one.

3. Pick the right mode

• Spot colors: logos, type, flat vector-style art. Every pixel prints one flat ink. Free.
• Simulated process: photos, painted or gradient art, especially on dark shirts. Inks blend with halftone dots. Areas that one ink already matches print that ink solid, so flat parts stay clean. Pro.
• Index: square dither pixels, no halftone screens, no angles, no moire. Very forgiving on press, and it likes a couple more colors. Free.
• 4-color process (CMYK): photos on white or light shirts with transparent process inks. Pro.
• New art is checked on load: flat art starts in Spot with Auto, photo or gradient art starts in Sim process. You can always switch.

4. Use the fewest screens that hold the look

• Auto (Spot) finds the smallest ink set that still matches the art. It ignores distressed grain, soft edges and darker shades of the same color, so a grungy one-color logo stays one color.
• The color count includes the underbase. "6 colors" on a dark shirt is the base plus 5 inks.
• + Highlight adds a highlight white (or a tinted second highlight). + Black adds a black detail screen. Both are quick ways to add pop without re-picking everything.
• Color Crunch folds the closest inks together until the job fits your screen count. Merge on a plate folds that one plate into another. Neither can be undone, so save them for the end.
• Solid on an ink locks it: areas that are that color print 100% with no dots. Great for big flat fills inside sim art.

5. Get the underbase right

• Choke the base 1 to 2 px so it never peeks out past the colors on top. More choke for coarse mesh or a loose press.
• Base strength (Sim): Light keeps the base thinner and back from the fades (softer hand, no halo). Full brings it right up to the ink (brightest color). Balanced is the default middle.
• Per-ink base: each ink card has Base Full, Half or None. Use None for inks that should sit dark and moody straight on the shirt.
• Per-area base: open the Base plate, select an area with the Wand or Lasso, set Amount and Apply. Good for flame tips and glows that should feather out without white behind them.
• Pull black takes the black out of the base so the shirt makes the black. Softer hand, richer shadows.
• Ink with no base on a dark shirt prints darker and duller, and the preview shows that. If a color looks muddy, check whether it has base under it. In Press check, turn the base off to see the difference.

6. Clean edges and plate edits

• Choke pulls a plate in 1 px per click (reductive). Stroke grows it out 1 px per click in its own ink (additive). They're opposites, so setting one clears the other. In Spot, the base grows under a stroke too.
• Speck cleanup (Finishing) removes bits too small to hold on mesh. 2 to 3 px is a good start for textured or distressed art.
• Wand and Lasso: click Edit on a channel, select with the Wand (each click adds; Shift starts fresh) or Lasso, then press Delete to erase, or Move or Copy to another plate. Esc clears the selection, Undo brings back the last edit.
• The Wand selects by color in the original art, so click on the color you want gone, not the background.

7. Halftones and films

• LPI: 45 suits manual presses, 55 is a good default for automatics. Keep every plate on the same angle (22.5 by default) to avoid moire.
• Minimum dot 20% holds on most mesh. Go 30% for manual presses, coarse mesh or a screen room that's still dialing in. Light tones still print, as small dots spaced further apart.
• Round dots are the safe default. Ellipse smooths midtones; Diamond and Square read sharper.
• Dot gain: turn it on only if your RIP does not already apply a gain curve.
• Posterize (3 to 6 levels) gives a clean, punchy sim look and hides gradient banding.
• Formats: EPS is the RIP standard. PSD gives one file with named spot channels for Photoshop. PDF is one page per plate. Use Pre-ripped dots if you print films straight from Photoshop or Illustrator without a RIP.
• Film marks add registration targets, a gray wedge and a job label (job, customer, location, print order, mesh) to every film, all in the same layout so they register.

8. Check it before you burn

• Press check builds the print hit by hit on the shirt color. Step through with Hit ◀ ▶, hit Play, or click any channel to turn it on or off. It's the fastest way to catch a bad base, a stray screen or a wrong print order.
• Compare wipes between your art and the sep preview. Zoom to 100% to see the real dots.
• Plates > Black film shows exactly what gets burned to each screen.
• Print order: later plates print over earlier ones. Use Earlier and Later on a plate to reorder; the films and preview follow.

9. Quick fixes

• White halo around colors: add base choke, lower Base strength, or set Base to Half on that ink.
• Colors look dull on a dark shirt: they probably have no base under them. Raise Base strength or set that ink to Base Full.
• A light color isn't printing: make sure an ink close to it is in the palette (Auto adds one when it covers a real area), or add it with Pick from art.
• Sim looks too busy: try fewer colors, lower Blend, or lock big flat colors with Solid.
• Specks and stray dots: raise Speck cleanup, choke the plate 1 px, or select them with the Wand and press Delete.
• Banding in gradients: try Posterize, or raise the color count a step.
• Feels slow on huge art: big files take longer to redraw. Separate at print size (about 300 DPI), not larger.

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