In order to produce a calibrated hyperspectral image, each individual image must be scaled by a calibration factor. The calibration factors were determined by comparing the image data at a reference location to direct radiometric measurements (PhotoResearch PR-650) of the light coming from this location. For the BearFruit1B and BearFruit1Y images, the reference location is labeled "R" in the image at right. When we acquired the BearFruit1Y image, we also measured spectra from three additional image regions, labeled "P" (pink), "T" (table), and "B" (box). The three plots on this page compare these additional spectra to the spectra derived from the BearFruit1Y image at the same locations. The agreement is generally good, although there are small deviations at 440 nm and 490 nm.