Spectral reflectance measurements of standard materials in laboratory setting - Denver, CO, July 8, 2022

Two spectroradiometers, a Malvern Panalytical Analytical Spectral Devices FieldSpec® 4 Hi-Res (hereafter referred to as ASD spectrometer) and a high sensitivity spectrometer, OCEAN-HDX-VIS-NIR®, from Ocean Optics (hereafter referred to as HDX) were used to collect reflectance measurements of materials in a controlled indoor setting at the USGS Spectroscopy Lab in Denver, Colorado on July 8, 2022 to enable spectrometer wavelength position comparisons.

The ASD spectrometer has a spectral range of 350 to 2500 nm. Malvern Panalytical reports bandpass values of 3 nm in the VNIR (visible and near infrared, 350 to 1000 nm) and 8 nm in the SWIR (shortwave infrared, 1001 to 2500 nm). The ASD collects 2151 channels of spectral data within a 22° field of view (Malvern Panalytical, 2024). The HDX spectrometer has a spectral range of 345 to 930 nm. Ocean Optics reports that the HDX bandpass varies between 0.75 to 1.2 nm depending on the wavelength. The HDX collects 2068 channels of spectral data within a 25.4° field of view (Ocean Optics, 2024).

Five standard reference materials with strong, narrow absorption features were measured for comparing the wavelength positioning of the two spectrometers. Ten measurements were collected of each standard reference material using both spectrometer instruments. All ten reflectance spectra collected using each instrument are provided here in two Comma Separated Value (.csv extension) text files, one file per instrument source: "20220708_LabSpectra_ASD.csv" and "20220708_LabSpectra_HDX.csv". We also provide an averaged reflectance spectrum per material and instrument, provided in two additional .csv files: "20220708_LabSpectra_ASD_averaged.csv" and "20220708_LabSpectra_HDX_averaged.csv".

References Cited:

Malvern Panalytical, 2024, ASD FieldSpec 4 Hi-Res: High Resolution Spectroradiometer, accessed July 18, 2024 at https://www.malvernpanalytical.com/en/products/product-range/asd-range/…

Ocean Optics, 2024, Ocean HDX Spectrometers, accessed July 18, 2024 at https://www.oceanoptics.com/product/ocean-hdx/