Transparency, translucency, and subsurface scattering
Making transparent, translucent, and subsurface-scattering materials read convincingly under your lighting.
What it is
Transparent materials let you see through them — glass, clean water, thin plastic — often distorted, tinted, or blurred. You paint both the material's own surfaces (edges, thickness, reflections) and the scene behind it, deciding how much it bends or softens that background.
Translucent materials let light through but not clear images. Frosted glass, wax, jade, thin cloth, petals, and skin glow when light passes through, but you can't see sharp details behind them. You show this with soft, diffused light spreading just inside the material — brighter near the light source, fading into the interior.
Subsurface scattering is how light enters a material, scatters beneath the surface, and exits elsewhere. It shows up as soft, saturated color in thin or backlit areas: ears glowing red against a bright sky, fingers lit from behind, wax lit up by a candle flame, leaves glowing green with the sun behind them. You control where this appears, how strong it is, and how it blends into regular shading.
All three sit on top of basic value and form. Even light-passing materials still have thickness, cast shadows, occlusion (tight darks in creases and overlaps), and a clear light direction. The work is balancing see-through, glow-through, and normal shading so the material reads clearly instead of turning into a vague light blob.
Why it matters
Treat everything as opaque and glass, water, skin, or fabric look painted-on and dead. Overdo the glow and forms collapse — faces look swollen, water and glass lose solidity. Get the balance right and you can sell eyes, skin, liquids, and lighting moments like backlit figures, candles, or underwater scenes.
You can check it when
- ✓You can paint the same object as opaque, transparent, and translucent — each version reads clearly at a glance.
- ✓Your glass or clear water shows both the object itself (edges, thickness, reflections) and what's behind it, without either fighting for attention.
- ✓Your backlit skin, leaves, or thin fabric show soft glow only in thin, light-facing areas, blending smoothly into normal shading.
- ✓You can dial subsurface scattering subtly on skin without making the whole face glow, and paint frosted or milky materials that feel solid, not ghostlike.