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Related papers: Estimating Sky Level

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In this paper we present a non-interactive algorithm to estimate a representative value for the sky background on CCD images. The method we have devised uses the mode as a robust estimator of the background brightness in sub-windows…

Astrophysics · Physics 2011-05-23 F. Patat

The Vera C. Rubin Observatory Wide-Fast Deep (WFD) sky survey will reach unprecedented surface brightness depths over tens of thousands of square degrees. Surface brightness photometry has traditionally been a challenge. Current algorithms…

Instrumentation and Methods for Astrophysics · Physics 2023-01-25 Lee S. Kelvin , Imran Hasan , J. Anthony Tyson

The low surface brightness (LSB) regime ($\mu_{g} \gtrsim 26$ mag arcsec$^{-2}$) comprises a vast, mostly unexplored discovery space, from dwarf galaxies to the diffuse interstellar medium. Accessing this regime requires precisely removing…

Astrophysics of Galaxies · Physics 2024-01-24 A. E. Watkins , S. Kaviraj , C. C. Collins , J. H. Knapen , L. S. Kelvin , P. -A. Duc , J. Román , J. C. Mihos

Estimating the true background in an astronomical image is fundamental to detecting faint sources. In a typical low-photon count astronomical image, such as in the far and near-ultraviolet wavelength range, conventional methods relying on…

Instrumentation and Methods for Astrophysics · Physics 2024-11-27 Pushpak Pandey , Kanak Saha

Computer vision techniques enable automated detection of sky pixels in outdoor imagery. In urban climate, sky detection is an important first step in gathering information about urban morphology and sky view factors. However, obtaining…

Computer Vision and Pattern Recognition · Computer Science 2019-12-30 Kerry A. Nice , Jasper S. Wijnands , Ariane Middel , Jingcheng Wang , Yiming Qiu , Nan Zhao , Jason Thompson , Gideon D. P. A. Aschwanden , Haifeng Zhao , Mark Stevenson

We describe a procedure for background subtracting Sloan Digital Sky Survey (SDSS) imaging that improves the resulting detection and photometry of large galaxies on the sky. Within each SDSS drift scan run, we mask out detected sources and…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Michael R. Blanton , Eyal Kazin , Demitri Muna , Benjamin A. Weaver , Adrian Price-Whelan

Outdoor scene parsing models are often trained on ideal datasets and produce quality results. However, this leads to a discrepancy when applied to the real world. The quality of scene parsing, particularly sky classification, decreases in…

Computer Vision and Pattern Recognition · Computer Science 2018-01-10 Cecilia La Place , Aisha Urooj Khan , Ali Borji

Inverse rendering of outdoor scenes from unconstrained image collections is a challenging task, particularly illumination/albedo ambiguities and occlusion of the illumination environment (shadowing) caused by geometry. However, there are…

Computer Vision and Pattern Recognition · Computer Science 2024-07-31 James A. D. Gardner , Evgenii Kashin , Bernhard Egger , William A. P. Smith

We present a new method to subtract sky light from faint object observations with fiber-fed spectrographs. The algorithm has been developed in the framework of the phase A of OPTIMOS-EVE, an optical-to-IR multi-object spectrograph for the…

Instrumentation and Methods for Astrophysics · Physics 2010-09-06 M. Rodrigues , H. Flores , M. Puech , Y. Yang , F. Royer

We apply the sky brightness modelling technique introduced and developed by Roy Garstang to high-resolution DMSP-OLS satellite measurements of upward artificial light flux and to GTOPO30 digital elevation data in order to predict the…

Astrophysics · Physics 2009-11-10 Pierantonio Cinzano , Cristopher D. Elvidge

Ground-based whole sky imagers (WSIs) are being used by researchers in various fields to study the atmospheric events. These ground-based sky cameras capture visible-light images of the sky at regular intervals of time. Owing to the…

Computer Vision and Pattern Recognition · Computer Science 2021-10-20 Mayank Jain , Navya Jain , Yee Hui Lee , Stefan Winkler , Soumyabrata Dev

Using the excellent observed correlations among various infrared wavebands with 12 and 60 micron luminosities, we calculate the 2-300 micron spectra of galaxies as a function of luminosity. We then use 12 micron and 60 micron galaxy…

Astrophysics · Physics 2014-10-13 M. A. Malkan , F. W. Stecker

Numerous ongoing and future large area surveys (e.g. DES, EUCLID, LSST, WFIRST), will increase by several orders of magnitude the volume of data that can be exploited for galaxy morphology studies. The full potential of these surveys can…

Astrophysics of Galaxies · Physics 2018-01-31 D. Tuccillo , M. Huertas-Company , E. Decencière , S. Velasco-Forero , H. Domínguez Sánchez , P. Dimauro

The sky is a major component of the appearance of a photograph, and its color and tone can strongly influence the mood of a picture. In nighttime photography, the sky can also suffer from noise and color artifacts. For this reason, there is…

Computer Vision and Pattern Recognition · Computer Science 2020-06-19 Orly Liba , Longqi Cai , Yun-Ta Tsai , Elad Eban , Yair Movshovitz-Attias , Yael Pritch , Huizhong Chen , Jonathan T. Barron

Imaging the atmosphere using ground-based sky cameras is a popular approach to study various atmospheric phenomena. However, it usually focuses on the daytime. Nighttime sky/cloud images are darker and noisier, and thus harder to analyze.…

Computer Vision and Pattern Recognition · Computer Science 2017-05-31 Soumyabrata Dev , Florian M. Savoy , Yee Hui Lee , Stefan Winkler

We demonstrate a new multi-wavelength technique for two-dimensional parametric modelling of galaxy surface-brightness profiles, which we have incorporated into the widely used software GALFIT. Our new method, named GALFITM, extends…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Marina Vika , Steven P. Bamford , Boris Haeussler , Alex L. Rojas , Andrea Borch , Robert C. Nichol

This report presents the results of a sky detection technique used to improve the performance of a previously developed partial differential equation (PDE)-based hazy image enhancement algorithm. Additionally, a proposed alternative method…

Computer Vision and Pattern Recognition · Computer Science 2018-03-13 Uche A. Nnolim

The development of sensitive large format imaging arrays for the infrared promises to provide revolutionary capabilities for space astronomy. For example, the Infrared Array Camera (IRAC) on SIRTF will use four 256 x 256 arrays to provide…

Astrophysics · Physics 2016-08-30 D. J. Fixsen , S. H. Moseley , R. G. Arendt

In hierarchical galaxy formation models, galaxies evolve through mergers and accretions. Tidally-disrupted debris from these processes can remain as diffuse, faint structures, which can provide useful insight into the assembly history of…

When viewed from above the Earth's atmosphere, the nighttime ultraviolet sky background is profoundly dark - up to 100 times fainter than the equivalent visible background as measured by groundbased telescopes. Because the UV background is…

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