HOW TO MEASURE THE SPECTRUM OF A COLOR USING AN Eye-One Pro AND Measure Tool (last edit: 25 April 2012) First, to provide spectral data, you need the Eye-One spectrocolorimeter. Note: The i1 Display cannot be used for these measurements. The i1 Display colorimeter does not have a built-in light source and cannot make measurements in reflection. Also, the i1 Display can only provide tristimulus data, such as XYZ or xyY, and cannot provide spectral data. Procedure: Preset: select the Tool/Configure Instrument menu and check the spectrum box. From there-on, your measured files should contain a spectra. Procedure: 1- Click on the Measure/Test page (large) icon 2- Select a custom TestChart size (24 zones, 4 zones per band) 3- Click to launch the measure 4- Select the Zone mode 5- Using the Eye-One, measure each patch using the provided plastic guide (the elliptically shaped one). Suggestion: start at the upper-left (dark-skin), then go by rows. Be careful not to slide the plastic instruments on your chart and ruin your chart. 6- When a chart is done, select "Save As" .txt format.