ABSTRACT
We developed a method for visualization of makeup finishing with structured lighting. By analyzing images with a sequence of projection patterns, reflectance and transmittance of the cosmetic foundation (FD) layer were extracted as spatial maps using the difference between the light spread of bare skin and made-up skin. The spatial maps reflect conditions and distribution of applied FD under real situations. By calibrating the relationship between optical properties and the amount of FD applied, the application amount distribution was also estimated. Additionally, we proposed approximation formulae to estimate the above values without images of bare skin. These formulae provide good agreement with the original formula for reflectance.
Subject(s)
SkinABSTRACT
In conventional psychophysical reverse correlation methods using white or pink noise, the luminance noise is added to every pixel. Thus, the image features correlated with perception are often biased toward local mean luminance. Furthermore, spatial frequencies and orientations are represented in the primary visual cortex, which forms the basis of various visual perception. In this study, we proposed a new reverse correlation method using noise that modulated the spatial frequency sub-band contrast and examined its properties in psychophysical experiments on facial skin lightness perception. In the experiment, we asked the observers to compare the perceived skin lightness in a paired comparison manner on face stimuli with increased or decreased spatial frequency sub-band contrasts at random spatial locations. The results showed that the contrasts in the eyes or irises were strongly and positively correlated with the perceived skin lightness in most sub-bands, demonstrating that the proposed method reiterated the findings of previous studies that the sparkle of the irises makes the skin appear lighter. Contrarily, the conventional reverse correlation method using pink noise images was applied to the skin lightness perception. The results indicated that only the local mean luminance in some skin regions, such as the forehead, was correlated with skin lightness perception. In summary, with the proposed method, we found some image features in the facial parts other than the skin mean luminance relevant to skin lightness perception, which are difficult to detect using the conventional method. They are considered complementary given that the proposed method and the conventional method extracted considerably different image features. It depends on the psychophysical tasks and stimuli which one is more appropriate.
Subject(s)
Contrast Sensitivity , Light , Correlation of Data , Humans , Noise , Visual PerceptionABSTRACT
We developed a method to estimate the reflectance, transmittance, and absorbance of a layer of cosmetic foundation (FD) applied to skin from the reflectance of bare skin and FD applied to skin under two measurement conditions using the translucency of skin. Conversely, using the relationship between the applied amount of FD and the reflectance of the FD layer, the applied amount could be estimated. These values could be measured stably regardless of the similarity of reflectance and color between bare skin and made-up skin. The measured values were taken from actual skin, which satisfies the condition of actual usage.
Subject(s)
Cosmetics/pharmacology , Skin/drug effects , Sunscreening Agents/pharmacology , Adult , Female , Humans , Light , Male , Middle Aged , Scattering, Radiation , Skin/metabolism , Skin Pigmentation/drug effects , Young AdultABSTRACT
An automated fluorescence protein sequencer using 7-methylthio-5-(2,1,3-benzoxadiazolyl) isithiocyanate (MTBD-NCS), a fluorescent Edman reagent, is developed by the modification of a commercial protein sequencer. The generated MTBD-thiohydantoin amino acids fluoresced strongly, whereas the by-products such as MTBD-thiocarbamoyl amino acids and MTBD-carbamoly amino acids did not fluoresce. A few interfering peaks were observed in the chromatogram and amino acid sequence was easily determined. The coupling and cyclization/cleavage reaction conditions and extraction conditions of generated MTBD-thiazolinone amino acids were optimized using an autonalyzer. Finally, the sequence of a synthetic peptide (25 pmol), leucine-enkephalin-Thr-amide, was determined and up to six residues were successively analyzed.