The sign of an accommodative response is provided by differences in chromatic aberration between under- and over-accommodated images. We asked whether these differences enable people to judge the depth order of two stimuli in the absence of other depth cues. Two vertical test edges separated laterally by an illuminated gap were presented to one eye with one edge at random distances relative to the other fixed edge. The fixed edge was at the same distance as two coplanar pre-fixation edges. In one condition, exposure duration was brief so that accommodation could not change. In other conditions exposure was prolonged and subjects either continued to fixate the fixed edge or changed their accommodation between the two test edges. The gap was illuminated with tungsten light or monochromatic light. Subjects could detect image blur of about 0.3 D with brief exposure for both types of light. However, they could detect depth order only in tungsten light with long exposure, with or without changes in accommodation.