Dataset for reproducing absorption spectra of methyl orange from the RGB values of microscopic images

The present dataset is related to the research paper entitled “Reproducing Absorption Spectra of pH Indicators from RGB Values of Microscopic Images” (Inagawa et al., 2020). The dataset contains microscopic images of aqueous methyl orange (MO), absorption spectra acquired with a spectrophotometer, loading spectra and calculation sheets for reproducing absorption spectra of aqueous MO from their RGB values of the microscopic images. The microscopic transmission images of the standard MO solutions at various pH conditions were acquired with a CMOS camera equipped with an invert microscope. Meanwhile, the loading spectra were obtained by principle component analysis of a series of absorption spectra of the standard solutions. The conversion matrix from RGB values in a region of interests (ROI) to score values were linear-algebraically determined from the RGB values and score values of the standard solutions. The absorption spectra of the sample solutions of which pH conditions are unknown were then reproduced by calculating the linear combination of the loading spectra with the score values obtained from the conversion process. Herein, the absorption spectra of MO are reproduced at various pH and ROI conditions.