Methods for fabricating sub-lithographic, nanoscale microchannels utilizing an aqueous emulsion of an amphiphilic agent and a water-soluble, hydrogel-forming polymer, and films and devices formed from these methods are provided. In the image exposing apparatus, a recording level setting unit calculates a recording level corresponding to a light amount level stored in a recording level light amount memory and sets the calculated recording level. Further, the subsequence matrix is processed to obtain a candidate subsequence matrix comprising a plurality of non-trivial subsequences.