Short answer
Soft proofing is previewing on a monitor how a file will look when printed to a specific condition: the software converts the colours through the output profile and back to the display, optionally simulating the paper's white and the ink's black. It is trustworthy for spotting out-of-gamut colours and shadow loss when the display is calibrated and viewed beside a print under controlled light; it cannot replace a contract proof for approving colour.
A soft proof chains two conversions. The document colour is first converted to the output condition — for example PSO Coated v3 — with the rendering intent you will use for real, which applies the same clipping or compression the press file will get. That CMYK result is then converted back to the display's profile, usually with absolute colorimetric intent when 'simulate paper colour' is on, so the paper's slightly blue or cream white and its limited black appear on screen. What you see is therefore the printable colour, not the original, with the press's white and black substituted for the monitor's.
Switching on paper simulation makes a crisp screen image suddenly look grey and flat. That is partly real — paper white is darker than a monitor's white and press black is much lighter than a panel's black — and partly adaptation: the eye was adapted to the monitor's white, which is still visible in the interface around the image. Viewed full-screen for a minute, or with a neutral grey interface, the image recovers most of its apparent contrast, just as a print does in hand. Judging a soft proof in a window surrounded by bright white menus exaggerates how dull the print will be.
The display must be calibrated and profiled; an uncalibrated wide-gamut panel shows the wrong colour before any proofing starts. Its white point should match the viewing light for prints (D50 for work to ISO print standards) and its luminance should roughly match paper under that light, not the 200 cd/m² or more many monitors run at. The room should be dim and neutral, and the print for comparison should sit in a D50 viewing booth. A display covering more of the press gamut helps too: an sRGB-only panel cannot show press cyan faithfully, so it will misrepresent exactly the colours you are checking.
A soft proof shows colorimetry, not material. It does not show gloss, texture, mottle, the way ink sits on uncoated fibres, or how the sheet looks under different lights. Optical brighteners glow differently under a monitor than under daylight-like light with UV. And a monitor cannot be measured with the same instrument and tolerances as a printed proof, so it has no agreed pass or fail. Soft proofs are the right tool for design decisions and quick checks; approval of colour-critical work still needs a hard proof made to ISO 12647-7 and verified with a control strip.
Why: The image is surrounded by the bright white interface, so the eye stays adapted to the monitor's white.
Fix: Use a neutral grey interface, view full-screen, and give your eyes a minute to adapt.
Why: The monitor is much brighter than paper in the viewing light, so shadows look open on screen.
Fix: Lower display luminance to match paper under the booth light before judging tone.
Why: The display's gamut is smaller than the press's in the cyan region, so the preview itself was clipped.
Fix: Proof on a wider-gamut display, or rely on a printed proof for cyans and blue-greens.
Each statement is labelled by kind — established fact, a standard’s requirement, observed market data, a convention, or Colourwise’s own interpretation or analysis — with the strength of the evidence behind it.
FactStrong evidence
Absolute colorimetric rendering reproduces the source paper colour, which is what allows a proof — soft or hard — to simulate the production paper's white.
Source: White Paper 40: Black-point compensation — theory and application
StandardStrong evidence
Print viewing conditions in the graphic arts are standardised on D50 light in ISO 3664, whose 2025 fourth edition replaced the 2009 edition referenced by the current offset and proofing standards.
Caveat: Only the catalogue records were checked; which viewing condition a particular contract specifies should be confirmed with the printer.
Source: ISO 3664:2025 Graphic technology and photography — Viewing conditions; ISO 13655:2017 Graphic technology — Spectral measurement and colorimetric computation for graphic arts images
Colourwise interpretationModerate evidence
Soft proofs are suitable for design decisions but not for contractual colour approval, because there is no agreed way to verify a displayed proof against press aims with the same instruments and tolerances as a printed contract proof.
Based on: ISO 12647-7 defines verification of printed proofs by measuring a control strip against characterisation data; a display image cannot be measured in the same way with a reflectance spectrophotometer.
Reviewed 29 September 2026. Colourwise summarises its sources in its own words and does not reproduce standards text or proprietary colour data. Spotted an error? Tell us.