The experimental method for in-phantom imaging and profiling the absorbed dose in neutron capture therapy has been improved. The method separates the contributions of the various secondary radiation components and is based on suitably designed gel dosimeters in the form of layers. The discrimination of the dose components is achieved by means of pixel-to-pixel manipulations of images obtained with gel dosimeters having different isotopic composition. Large dose images are obtainable with this method, because the layer geometry of dosimeters avoids sensible variation of neutron transport due to the isotopic composition of gel. Operation modalities aimed at attaining more reliable results have been studied. Some results, together with the results of punctual measurements performed with conventional dosimeters and with MC calculations, are here reported.