1. A method of determining a film coating thickness on a substrate and/or amount of one or more compositional ingredients of said film coating comprising: irradiating said film coating with infrared energy over a spectrum of wavelengths, said irradiating performed with an IR source; detecting said infrared energy reflected from said film coating on said substrate over said spectrum of wavelengths, said detecting performed with an IR spectrometer; performing multivariate analysis on the spectrum of said reflected infrared energy, said multivariate analysis comprising relative changes in said spectrum with respect to a reference spectrum; comparing results of said multivariate analysis with a predetermined calibration of model infrared energy spectra comprising said spectrum of wavelengths collected from a plurality of model film coatings, said model infrared energy spectra calibrated with respect to model film coatings comprising known film coating thickness and/or amount of one or more compositional ingredients; and, determining said film coating thickness and/or amount of one or more compositional ingredients of said film coating based on said predetermined calibration.