A method of detecting oxygen and/or chemical content in a subject, comprising generating at least one spectral image of the subject; generating at least one spectral image of a reference object; comparing spectrum from the subject image to the reference image to thereby reveal the relative oxygen content of the subject. A system for determining the level of oxygenation of the blood of a subject body part comprising: a hyperspectral image generator for generating a plurality of spectral images; an image capture device for capturing the spectral images; a processor for generating hyperspectral image cubes such that the spectrum of the body part is extracted and normalized using the spectrum from the reference object to cancel out the spectral response of the light source and the imager; said processor comparing spectral from a subject image to reference images to thereby reveal the relative oxygen content of the subject.