A great open-source spectrometer built the same way is available from PublicLab here: http://store.publiclab.org/products/desktop-spectrometry-kit-3-0 http://st

A great open-source spectrometer built the same way is available from PublicLab here: http://store.publiclab.org/products/desktop-spectrometry-kit-3-0 http://store.publiclab.org/products/desktop-spectrometry-kit... (or you can just build it yourself using their designs on the Wiki). PublicLab also has a repository for spectra so you can calibrate and compare with others.