Methods (300, 1000) of determining a light scattering property of a medium (152), are disclosed. The medium (152) is illuminated through a test pattern (e.g., 155, 510), the test pattern (155, 510) comprising at least one region containing a first pattern with substantial variation in two orthogonal directions at one scale. The test pattern (300, 1000) further comprises at least one other region containing the first pattern at a different scale. The light reflected from the illuminated medium (152) through the test pattern is measured to capture an image of the illuminated medium. A light scattering property of the medium (152) is determined based on the measured light.