Aspects of blending data detected by a monochromator over multiple wavelength ranges is described herein. In one embodiment, the monochromator includes a diffraction grating, a grating drive motor that rotates the diffraction grating to provide, by diffraction of broadband light, first dispersed wavelengths of light and second dispersed wavelengths of light, a detector that detects a first reflection from the first dispersed wavelengths of light and a second reflection from the second dispersed wavelengths of light, and processing circuitry that blends data values from the first reflection and data values from the second reflection together to provide a spectrum of combined data values. By blending data detected over multiple ranges, measurements of relatively high precision and quality can be provided over a wider spectral range.