The product itself disappointed me. A cold, we perceive with light reflections masked areas (path yellow balls, characters). A hot these areas are not perfectly "unmasked". These areas are whiter than the rest of the cup: so that the paths of yellow dots are blurred in maquées areas and gives the impression of having lines (linked to yellow shades - shiny black mask - black the cup). I have no idea of the establishment of processes for hidden areas, but I would have preferred that all paths are hidden labyrinth (although there is nothing to hide) not able to guess cold the placement of objects and avoid hot line effect in the paths of yellow dots.