The colors are real, mostly generated by thin-film interference depending on the thickness of the layers. Some people boost the saturation to make it more drama

The colors are real, mostly generated by thin-film interference depending on the thickness of the layers. Some people boost the saturation to make it more dramatic, but I think John's photos are natural. There's a color chart here: http://www.htelabs.com/appnotes/sio2_color_chart_thermal_silicon_dioxide.htm http://www.htelabs.com/appnotes/sio2_color_chart_thermal_sil...