The functions provided below result from our research into human cone spectral sensitivities and luminous efficiency. These versions are provided to either 8 dp for logarithmic data or to 9 sf for linear data. They provide a consistent set of colorimetric and photometric data that can be used to model and predict normal and dichromatic colour vision for standard target sizes of 2-deg or 10-deg in diameter. The data are provided either as ascii csv (comma separated values) files, as ascii xml (extensible markup language) files, as html tables—which appear in your browser window, or as dynamic graphical plots. Select the data format, the data stepsize and the data units and click the "Submit" button. For further details and references click . To return to the standard functions to 5 dp or 6 sf click here.