Summary

Blotter Builder's editor works entirely in RGB — there is no CMYK mode, toggle, or input anywhere in the interface. Print-specific color conversion happens automatically, server-side, at export time. Two separate, preview-only aids exist for judging print color on screen: Realistic view (paper texture only) and Approximate soft proof (a rough color-shift simulation) — neither is a calibrated match to the actual export.

Use it when

  • You want to know whether you're working in RGB or CMYK while designing.
  • You want a rough on-screen sense of how toner-on-uncoated-stock printing might shift your colors.
  • You're deciding how much to trust on-screen color before ordering.

Before you begin

Nothing to prepare. Color authoring (the Color panel's Fill/ Stroke, hex, RGB, and HSV fields) is available regardless of format or layer selection, as covered in Fill, stroke, palette, and color.

Steps

  1. Design using the Color panel as usual — all values are RGB (hex, R/G/B, H/S/V). There is no CMYK input anywhere in the editor.
  2. Optionally switch View to Realistic to preview paper texture and the perforation pattern — this does not change color.
  3. Optionally enable Approximate soft proof in Options for a rough preview of how toner-on-uncoated-stock printing can shift color.
  4. Check Color profile in Export before ordering or exporting — it currently reads Uncalibrated.
  5. Read the Print color note in Export for the full explanation of what's placeholder and what isn't yet.

What changes

  • Approximate soft proof applies a CSS filter to the whole stage — confirmed directly: enabling it added contrast(0.92) saturate(0.85) sepia(0.08) brightness(0.97) to the stage element, and disabling it removed the filter entirely (filter: none). It is applied at the display layer, not to the underlying image data — sampling the canvas's actual pixel values directly showed no change with the toggle on or off.
  • Realistic view is a separate control from soft proof — its own tooltip states it "adds paper texture and a perforation pattern for on-screen preview only" and does not affect color.
  • Neither preview aid uses the actual export color profile. The app's own tooltip is explicit: Approximate soft proof ... is also preview-only and does not use the placeholder ICC profile. So even the "placeholder" profile used at export time is not what you're previewing when soft proof is on — it's a separate, cruder approximation of a different approximation.

Print note

This entire topic is the print note. The editor authors in RGB; the actual print-specific conversion — described in the app's own marketing copy as a "print-profile color conversion" applied "server-side, embedded straight into the PDF" — happens only at export, not in the editor. The Export panel's own text: Print export uses a placeholder color profile (standard sRGB stand-in) — not yet calibrated to the Canson 140lb cold-press + VersaLink C8000 combo. Color is not final. Treat any color you see on screen — soft-proofed or not — as provisional until that placeholder profile is replaced with a calibrated one.

Warnings and limits

  • There is no calibrated soft proof available yet. Both on-screen aids — Realistic view and Approximate soft proof — are explicitly disclosed as approximations, and soft proof specifically does not even use the same placeholder profile export uses. Do not treat either as a reliable preview of final printed color.
  • Color profile: Uncalibrated is shown as a neutral, informational badge (plain dl-badge styling, muted gray) rather than a red warning badge like the DPI LOW indicator — it's persistent, expected status right now, not an error state you can clear by taking an action in the editor.
  • Because there is no CMYK mode in the editor, you cannot preview out-of-gamut colors or CMYK conversion shifts before export. Any such shift happens invisibly during the server-side export step.

Desktop and mobile

Approximate soft proof (in the Options panel/sheet) and Color profile (in the Export panel/sheet) are reachable the same way on desktop and mobile — both were confirmed present in their respective mobile sheets.

Troubleshooting

Symptom Likely cause Recovery
Colors on screen don't match what printed Neither on-screen preview is calibrated yet — this is expected, disclosed behavior Don't rely on screen color for final judgment until the profile is calibrated; order a proof if color accuracy matters
Can't find a CMYK color mode It doesn't exist in the editor — all authoring is RGB Design in RGB; CMYK conversion happens automatically at export
Approximate soft proof doesn't look like it's doing anything The shift is subtle by design (contrast 0.92, saturation 0.85) — check Options to confirm the checkbox is actually enabled Toggle it off and on to compare, or check the artboard's overall warmth/contrast shift
Unsure whether Realistic view or Approximate soft proof is responsible for a visual change They're independent controls — Realistic adds paper texture only; soft proof shifts color only Toggle each independently to isolate which one is active

Related topics

  • Fill, stroke, palette, and color
  • Grid and realistic preview
  • Effective DPI and resolution warnings
  • Print PDF + Silhouette cut guide

Verification note

Verified against Blotter Builder on 2026-07-20.

Source notes

Primary observations — all from the live application at https://blotterbuilder.tdl.fyi, 2026-07-20:

  • Observed — a full-page HTML search for the literal string "CMYK" returned no matches anywhere in the application, including expanded info-toggle text.
  • Observed — the Color panel's fields are Hex, Hue, H/S/V, and R/G/B only.
  • Observed — enabling Approximate soft proof with an image placed via Fill canvas added filter: contrast(0.92) saturate(0.85) sepia(0.08) brightness(0.97) to the stage element's computed style (._stage_... container, parent of .canvas-container); disabling it set the filter back to none.
  • Observed — sampling the same canvas pixel via getImageData before and after toggling Approximate soft proof, in both Vector grid and Realistic view modes, showed identical values each time, confirming the effect is a display-layer CSS filter, not a change to the underlying image data.
  • Observed — full text of the About approximate soft proof note: Approximate soft proof — illustrates the general kind of shift toner-on-uncoated-stock printing can produce, not a calibrated match to the placeholder profile.
  • Observed — full text of the realistic-view tooltip: Realistic mode adds paper texture and a perforation pattern for on-screen preview only. It helps you judge composition on blotter-style stock; exported files are unchanged. Approximate soft proof (in Options) is also preview-only and does not use the placeholder ICC profile.
  • Observed — the Color profile: Uncalibrated badge's computed style: class dl-badge (not dl-badge--danger), color rgb(148, 143, 131) — a neutral muted gray, distinct from the red dl-badge--danger styling used for the DPI LOW warning.
  • Observed — full text of the Print color note: Print export uses a placeholder color profile (standard sRGB stand-in) — not yet calibrated to the Canson 140lb cold-press + VersaLink C8000 combo. Color is not final.
  • Observed — at 390 × 844, Approximate soft proof was present in the Options sheet and Color profile was present in the Export sheet.

Verification log

Viewport Steps tested Observed result Date
1280 × 800 Search full page HTML for "CMYK" No matches found 2026-07-20
1280 × 800 Enable Approximate soft proof, read stage element's computed filter contrast(0.92) saturate(0.85) sepia(0.08) brightness(0.97) 2026-07-20
1280 × 800 Disable it, re-read filter none 2026-07-20
1280 × 800 Sample canvas pixel data with soft proof on vs. off, in both view modes Identical pixel values in all cases 2026-07-20
1280 × 800 Read Color profile badge computed style Plain dl-badge, muted gray — not the red danger style 2026-07-20
390 × 844 Open Options sheet, then Export sheet Approximate soft proof and Color profile both present 2026-07-20