Clear daytime skies persistently display a subtle local maximum of radiance near the astronomical horizon. Spectroradiometry and digital image analysis confirm this maximum's reality, and they show that its angular width and elevation vary with solar elevation, azimuth relative to the Sun, and aerosol optical depth. Many existing models of atmospheric scattering do not generate this near-horizo...

The UVB emission from ten different types of 'UVA fluorescent lamp' has been measured by spectroradiometry. The mean ratio of UVB emission to UVA emission was found to be 0.94 +/- 0.35 (1 SD)%. By weighting the spectral irradiance of each lamp by the DIN standard erythemal curve, the mean erythemally effective UVB emission (normalised to 297 nm), expressed as a percentage of the UVA emission, w...

We used spectroradiometry to rapidly and nondestructively predict the nicotine content in fluecured tobacco leaves and obtained hyperspectral images of tobacco leaves during the squaring development stage at field conditions. We tested the nicotine content in the lab and analyzed correlations between 28 hyperspectral characteristic parameters and the nicotine content of tobacco leaves to establ...

The investigation of spatially-resolved solar plasma features in terms of radiometric measurements requires concepts different from those useful for full-Sun observations. After a definition of the relevant physical quantities, formulae are derived for studies of optically-thick and optically-thin plasmas observed with both spectral and spatial resolution. Simple examples of their applications ...