VectorPaint gradient proof sheets: compare banding, transparent ends and real display

English translation of the Chinese original, translated on 2026-10-27. Original publication dates, attribution, code and version notes are retained.

A smooth editor preview still needs output inspection. Build a gradient proof sheet that separates colour changes, transparency and display size. It records observations without guaranteeing identical colour across screens, printers or software or providing colour-certification results.

Limit the comparison to three questions

Use three equal rectangles for a two-colour gradient, same-colour fade and short transition. Reserve parameter notes on a 1200 by 800 pixel canvas. Exclude unrelated effects. Define banding, transparent-end behaviour and reduction as separate questions, changing one variable at a time and preserving a baseline source.

Set an explicit direction for the two-colour proof

Use a left-to-right linear gradient and record endpoint colours and stops. Keep rectangle size fixed while editing. Nearby solid endpoint swatches help visual comparison but are not instrument measurements. Test any extra stop separately; closely spaced stops can create abrupt transitions rather than improve smoothness.

Check the transparency proof on two backgrounds

Fade one colour toward transparency and inspect light and dark backing panels. A transparent end reveals underlying content; a white end may indicate a white stop or object. Manage test backgrounds explicitly before transparent export. Record background-dependent appearance without automatically diagnosing corruption, since transparency naturally composites with its background.

Inspect an intentionally short transition

Concentrate the same endpoint transition into a shorter region to distinguish intentional steepness from output banding. Compare source and equal-size export with unchanged opacity, background and geometry. Record any added-stop effects explicitly rather than attributing every unwanted gradient to the format.

Compare exports at the same display size

Export required formats and compare at equal display size, recording renderer/version. Confirm raster dimensions before blaming enlarged pixels on gradient settings. A second trusted renderer can help, using the same export round. Name proof type, size and revision clearly to avoid comparing stale files with updated sources.

Record printed results separately

For paper use, print a proof and record paper, process and observed differences. Screen approval does not guarantee print matching or professional prepress calibration. Confirm file and scaling before discussing adjustments with the producer. Retain earlier sources and previews and reproof one change at a time.

Keep conclusions tied to reproducible proofs

Record colours, transparency, direction, dimensions, renderer and observations for each proof. Scope claims to tested conditions and separate preference from compatibility issues. Keep the labelled sheet with its source for future background changes. Delivery notes need use, tested conditions and remaining differences, not implementation details.

Rule out settings and scaling before diagnosing bands

For one striped row, inspect its intentional transition and stop spacing. For all rows, check scaling, versions and another renderer. Diagnose white fades through stop colour and backing objects. Inspect strokes for borders. Re-export and reopen after each change, retaining reproducible problem proofs rather than randomly recolouring.