High speed cameras have the ability to detect luminance variation due to the alternating current of illuminations. On the basis of the luminance variation, this paper proposes a method to estimate an image of when one of the illuminations is nonluminous. If the nonluminous illumination is the source of specular reflection, the estimated image only includes diffuse reflection components of other illuminations. Experimental results in various conditions show that specular reflection components are eliminated without the displacement of a camera or an illumination.