Object Source Lighting (OSL)
Paint the effect of a light source on the model, like a glowing sword or magic spell illuminating nearby surfaces.
Object Source Lighting simulates light being emitted from a source on the model itself — a glowing weapon, a torch, magical energy, glowing eyes, or plasma coils. You paint the light source very bright, then paint a gradient of that light color onto surrounding surfaces, fading with distance. Done well, it makes models look dramatically lit. Done poorly, it looks like someone smeared paint on the model.
Best For
Recommended Paint Types
Step-by-Step
Decide where your light source is and what color it emits.
Paint the light source itself very bright — near white at the center.
Identify which surfaces the light would hit based on proximity and angle.
On nearby surfaces, apply glazes of the light color over the existing paint.
Closer surfaces get more coats (brighter). Further surfaces get fewer (dimmer).
The effect should fade to nothing within a realistic distance.
Increase contrast by making surfaces facing AWAY from the light slightly darker than normal.
Add a final white/near-white spot at the very center of the light source.
Pro Tips
Less is more. Subtle OSL looks way better than overdone OSL.
The light color should tint the receiving surface, not replace it entirely.
OSL works best on models that are otherwise darkly painted — the contrast sells the effect.
Fluorescent paints can make the light source glow under UV for extra impact.
Common Mistakes
Making the glow too strong — it should be subtle on most receiving surfaces.
Light reaching surfaces it physically couldn't (going around corners, through objects).
The light source itself not being bright enough — it needs to be the brightest point.
Applying OSL over bright basecoats — it's hard to see. Works best over dark schemes.