Finish changes perceived colour
Matte paint scatters reflected light more broadly. Glossy or satin paint creates stronger highlights that move with the viewer. On a curved shoulder pad, those reflections can make two nominally close colours look different even when a flat digital swatch suggests otherwise.
Varnish can bring finishes closer, but it does not necessarily erase differences in surface texture or transparency. Record the intended final varnish when evaluating a substitution.
Opacity and coverage are separate decisions
Opacity describes how much the dried paint film hides what is beneath it. Coverage is the practical result you get after a given application: pigment strength, viscosity, thinning, layer thickness, brushwork, and undercoat all contribute. A transparent colour may be highly saturated and still require the previous layer to build its final appearance.
Manufacturer technical charts show why a colour label alone is insufficient. Golden’s SoFlat chart lists opacity/transparency, gloss, viscosity, Lab values, and tint strength as separate properties for each colour. Liquitex similarly distinguishes opaque, semi-opaque, and transparent categories by how much light passes through a layer.
| Paint behaviour | What drives the result | Substitution priority |
|---|---|---|
| Opaque standard acrylic | Hiding power, thinning, levelness, finish | Coverage and finish before tiny ΔE gains |
| Wash or shade | Flow, surface tension, staining, pigment load | Recess behaviour and tint strength |
| Transparent one-coat paint | Transparency, pooling, undercoat, reactivation | System behaviour and recommended primer |
| Glaze or ink | Tint strength, transparency, binder, sheen | Dilution response and layer control |
| Metallic | Particle size, reflectance, coverage, binder tint | Metallic effect and value before flat swatch |
Undercoat is part of the colour
An opaque paint reduces the influence of the primer as layers build. A transparent product deliberately preserves it. The same bottle can produce a light, saturated result over white and a much darker result over black. That means a screen value cannot be interpreted without the layer structure.
When testing a replacement, use the same primer colour and surface. If the original recipe used a zenithal undercoat, reproduce the light-to-dark pattern rather than testing on a single flat chip.
Why BrushForge separates behaviour families
The public snapshot dated 10 July 2026 classifies 2,941 records into seven families: 2,154 opaque, 274 metallic, 301 single-coat, 148 wash, 42 ink, 10 glaze, and 12 other translucent. An ordinary compatible cross-brand match must share the source family.
This is a guardrail, not a complete material model. A wash is not treated as interchangeable with an ink, glaze, or Contrast-, Speedpaint-, or Xpress-style product. Even inside one family, opacity, binder, flow, drying, sheen, and recommended use can differ.
Hue bias appears in mixtures and thin layers
Two opaque swatches can look close at full strength yet diverge when mixed with white or thinned into a glaze. Pigment composition and tint strength affect the path between colours. If the translated recipe relies on mixing or glazing, test the mixture—not only each colour straight from the bottle.
A compact behaviour test
- Prepare two test areas with the intended primer.
- Apply one normal layer of the original and candidate at similar consistency.
- Record how much undercoat remains visible.
- Add the planned second coat, wash, or glaze.
- Let both dry fully; compare colour, sheen, texture, and edge control.
- Apply the intended varnish to a portion of each test.
Sources
- Golden Artist Colors: SoFlat technical chart, showing opacity, gloss, viscosity, Lab, and tint strength as distinct properties.
- Golden Artist Colors: Fluid Acrylic Colors, on formulation-related gloss and opacity variation.
- Liquitex: acrylic painting terms, including opacity and transparency definitions.
- BrushForge behaviour families and limitations.