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Wavelength Calibration  NCAVEO concrete reference target

The Field Spectroscopy Facility and National Physical Laboratory provided on site calibration services during the NCAVEO experiment

The Field Spectroscopy Facility and National Physical Laboratory provided on site calibration services during the first week of the NCAVEO experiment being run from 12th to 23rd June 2006 at Chilbolton Observatory , Hampshire, England. One of the aims of NCAVEO was to "Quantify the uncertainty in remote sensing physical measurements" (P.I. Dr. Karen Anderson). NCAVEO offered a unique opportunity to do this by bringing a large number of field spectrometers and reference panels together for comparison and inter-calibration. FSF set up a temporary dark room facility at Chilbolton Observatory at the start of the NCAVEO experiment and performed wavelength quality assurance checks on the spectrometers which were to be used by a number of researchers to acquire field data. Reflectance measurements from sixteen reflectance panels were also taken by FSF for comparison with a calibrated panel supplied by NPL. In addition, NPL provided an integrating sphere, referenced to an NPL radiance standards. The integrating sphere was used to calibrate radiance measurements on all spectrometers being used. The wavelength, radiance and panel reflectance data will allow all the spectrometers and reference panels to be characterised and compared and variances in measurements defined. In total three ASDs, three GERs and 5 Ocean Optics spectrometers, an irradiance goniometer and sixteen reference panels were calibrated prior to being used in the field. In addition, FSF personnel assisted in the field campaign, using FSF and Newcastle University spectrometers, to acquire data over ground based reference targets during Environment Agency, ARSF and satellite over passes.