frosted glass effect

frosted glass effect applied to the studio's source frame — beforefrosted glass effect applied to the studio's source frame — afterSourceEffect

01/ ORIGIN

Frosting is a surface treatment, not a material: acid or abrasive roughens one face of otherwise clear glass so light scatters on its way through. Nineteenth century builders used it wherever a room needed light without a view, in bathroom windows, office partitions and shop doors. The important property is that it never stops being transparent. It only destroys the ordering of what passes, which is why a shape pressed against it resolves and a shape a foot away does not.

02/ SWEEP

SCALE sweep

SCALE 1: a lightly etched surface, detail still mostly readable
SCALE 1SCALE 1: a lightly etched surface, detail still mostly readable
SCALE 2: the default, form legible but detail scattered
SCALE 2SCALE 2: the default, form legible but detail scattered
SCALE 8: heavily roughened, only the largest shapes surviving
SCALE 8SCALE 8: heavily roughened, only the largest shapes surviving

03/ SPEC

This effect displaces each pixel by a randomised local offset and blends the result, imitating refraction through a roughened surface rather than simply blurring. SCALE runs from 1 to 8 pixels with a default of 2 and sets the size of the surface perturbation, which controls how far detail is scattered and therefore how obscured the subject becomes. REFRACT from 0 to 1 sets displacement strength, and DISPERSION is an advanced control that splits the offset per channel for a prismatic edge. In kott it renders in natural colour so scattered hue stays visible.

SCALE1 to 8 · default 2
REFRACT0 to 1 · default 0.5

04/ FAQ

What is a frosted glass effect?
A frosted glass effect displaces pixels by randomised local offsets, imitating light scattering as it passes through a roughened but still transparent surface.
What is the difference between frosted glass and blur?
A blur averages neighbouring pixels, losing light information. Frosting displaces them, so all the light still arrives but in the wrong order, which is why edges pressed close still resolve.
How do I keep the subject recognisable?
Keep SCALE at 1 or 2 and REFRACT below 0.5. Larger perturbations scatter facial features past recognition, which is often the point in real architectural glass.