Using 180 degrees field-of-view (full-sky) imaging polarimetry, we measured the spatiotemporal change of the polarization of skylight during the total solar eclipse on 29 March 2006 in Turkey. We present our observations here on the temporal variation of the celestial patterns of the degree p and angle alpha of linear polarization of the eclipsed sky measured in the red (650 nm), green (550 nm)...

The profit of low-cost, multispectral imaging systems in estimating spectral power distributions has been widely studied. There are various mathematical methods available (PCA, Wiener’s estimation method, spline interpolation, MDST, among others) which permit the accurate reconstruction of a spectrum from the response of a small set of sensors. One important issue in this task is the influence ...

In this paper, we present a method to model shadows in outdoor scenes. Here, we note that the shadow areas correspond to the diffuse skylight which arises from the scattering of the sunlight by particles in the atmosphere. This yields a treatment in which shadows in the image can be viewed as a linear combination of scattered light obeying Rayleigh scattering and Mie theory. This allows for the...

Different classes of photoreceptors (PRs) allow animals to perceive various types of visual information. In the Drosophila eye, the outer PRs of each ommatidium are involved in motion detection while the inner PRs mediate color vision. In addition, flies use a specialized class of inner PRs in the "dorsal rim area" of the eye (DRA) to detect the e-vector of polarized light, allowing them to exp...

Many insects are able to detect the polarization pattern of the blue sky and use this capability for spatial orientation (Wehner R 1984, Annu. Rev. Entomol. 29, 277-298; Wehner R, Michel B and Antonsen P 1996, J. Exp. Biol. 199, 129-140). Ommatidia specialized to detect skylight polarization are confined to a small dorsal rim area (DRA) of the compound eye. The desert locust Schistocerca gregar...

NO2 Profile Retrieval using airborne multi axis UV-visible skylight absorption measurements over central Europe M. Bruns, S. A. Buehler, J. P. Burrows, A. Richter, A. Rozanov, P. Wang, K.-P. Heue, U. Platt, I. Pundt, and T. Wagner Institute of Environmental Physics, University of Bremen, P.O. Box 33 04 40, 28359 Bremen, Germany Institute of Environmental Physics, University of Heidelberg, Im Ne...

A new system to measure the natural skylight polarized radiance distribution has been developed. The system is based on a fish-eye lens, CCD camera system, and filter changer. With this system sequences of images can be combined to determine the linear polarization components of the incident light field. Calibration steps to determine the system 's polarization characteristics are described. Co...

This paper presents complementary flyover and surface exploration for reconnaissance of planetary point destinations, like skylights and polar crater rims, where local 3D detail matters. Recent breakthroughs in precise, safe landing enable spacecraft to touch down within a few hundred meters of target destinations. These precision trajectories provide unprecedented access to bird’s-eye views of...

Abstract The skylight on the roof of an atrium can be popular for commercial malls to illuminate core area building. However, solar radiation and its heat get into building together with daylight, causing excessive cooling load. This paper studies daylighting energy performances coverage air-conditioned atriums in hot humid regions. performance different heights, glass types ratios are studied....

The Belt of Venus (or antitwilight arch) is a reddish band often seen above the antisolar horizon during clear civil twilights, and immediately beneath it is the bluish-gray earth's shadow (or dark segment) cast on the atmosphere. Although both skylight phenomena have prompted decades of scientific research, surprisingly few measurements exist of their spectral, colorimetric, and photometric st...