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Point spread function (PSF) engineering of the emitter can code higher spatial frequency information of an image to break diffraction limit but suffer from the complexed optical systems. Here we present a robust strategy to simultaneously…

Optics · Physics 2021-02-23 Chaohao Chen , Baolei Liu , Yongtao Liu , Jiayan Liao , Xuchen Shan , Fan Wang , Dayong Jin

Observations close to the diffraction limit, with high Strehl ratios from Adaptive Optics (AO)-assisted instruments mounted on ground-based telescopes are a reality and will become even more widespread with the next generation instruments…

Instrumentation and Methods for Astrophysics · Physics 2023-10-23 Matteo Simioni , Carmelo Arcidiacono , Andrea Grazian , Marco Gullieuszik , Elisa Portaluri , Benedetta Vulcani , Roland Wagner , Anita Zanella

Camera pose estimation is a long-standing computer vision problem that to date often relies on classical methods, such as handcrafted keypoint matching, RANSAC and bundle adjustment. In this paper, we propose to formulate the Structure from…

Computer Vision and Pattern Recognition · Computer Science 2024-01-26 Jianyuan Wang , Christian Rupprecht , David Novotny

Point Spread Function (PSF) for imaging through inhomogeneous refractive medium, such as atmospheric turbulence is bounded by three constraints [Charnotskii, Opt. Eng., 52, 04600, (2013)]. PSF is non-negative, band-limited, and the third…

Optics · Physics 2022-07-06 Mikhail Charnotskii

Context. Most popular algorithms in use to remove the effects of a telescope's point spread function (PSF) in radio astronomy are variants of the CLEAN algorithm. Most of these algorithms model the sky brightness using the delta-function…

Instrumentation and Methods for Astrophysics · Physics 2017-12-18 L. Zhang , S. Bhatnagar , U. Rau , M. Zhang

In this communication are presented rigorous and approximate analytical expressions of the Point Spread Function (PSF) and Field of View (FoV) achievable by multi-aperture Fizeau interferometers, either of the imaging or nulling types. The…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 F. Henault

Context. Adaptive optics (AO) systems greatly increase the resolution of large telescopes, but produce complex point spread function (PSF) shapes, varying in time and across the field of view. This PSF must be accurately known since it…

We present an algorithm to derive difference images for data taken with the JWST with matched point-spread functions (PSFs). It is based on the saccadic fast Fourier transform (SFFT) method but with revisions to accommodate the rotations…

Instrumentation and Methods for Astrophysics · Physics 2024-04-30 Lei Hu , Lifan Wang

Monocular depth estimation is still an open challenge due to the ill-posed nature of the problem at hand. Deep learning based techniques have been extensively studied and proved capable of producing acceptable depth estimation accuracy even…

Image and Video Processing · Electrical Eng. & Systems 2022-04-15 Mazen Mel , Muhammad Siddiqui , Pietro Zanuttigh

The filtering of a Markov diffusion process on a manifold from counting process observations leads to `large' changes in the conditional distribution upon an observed event, corresponding to a multiplication of the density by the intensity…

Optimization and Control · Mathematics 2019-11-01 Simone Carlo Surace , Anna Kutschireiter , Jean-Pascal Pfister

Current and future imaging surveys will measure cosmic shear with a statistical precision that demands a deeper understanding of potential systematic biases in galaxy shape measurements than has been achieved to date. We investigate the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 J. E. Meyers , P. R. Burchat

Ground based optical telescopes are seriously affected by atmospheric turbulence induced aberrations. Understanding properties of these aberrations is important both for instruments design and image restoration methods development. Because…

Instrumentation and Methods for Astrophysics · Physics 2020-04-08 Peng Jia , Xuebo Wu , Yi Huang , Bojun Cai , Dongmei Cai

The aim of Shape From Shading (SFS) problem is to reconstruct the relief of an object from a single gray level image. In this paper we present a new method to solve the problem of SFS using Machine learning method. Our approach belongs to…

Computer Vision and Pattern Recognition · Computer Science 2016-07-13 Lyes Abada , Saliha Aouat

We present an analysis of six independent on-sky datasets taken with the Keck-II/NIRC2 instrument. Using the off-axis point spread function (PSF) reconstruction software AIROPA, we extract stellar astrometry, photometry, and other fitting…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Sean K. Terry , Jessica R. Lu , Paolo Turri , Anna Ciurlo , Abhimat Gautam , Tuan Do , Michael P. Fitzgerald , Andrea Ghez , Matthew Hosek , Gunther Witzel

Image subtraction in astronomy is a tool for transient object discovery and characterization, particularly useful in wide fields, and is well suited for moving or photometrically varying objects such as asteroids, extra-solar planets and…

Instrumentation and Methods for Astrophysics · Physics 2013-01-09 Steven Hartung

The ultimate goal of the "Pi of the Sky" apparatus is observation of optical flashes of astronomical origin and other light sources variable on short timescales. We search mainly for optical emission of Gamma Ray Bursts, but also for…

Instrumentation and Methods for Astrophysics · Physics 2011-11-02 Lech Wiktor Piotrowski

This paper describes a fast and accurate method for obtaining steerable principal components from a large dataset of images, assuming the images are well localized in space and frequency. The obtained steerable principal components are…

Computer Vision and Pattern Recognition · Computer Science 2018-08-10 Boris Landa , Yoel Shkolnisky

We present a new shear estimator for weak lensing observations which properly accounts for the effects of a realistic point spread function (PSF). Images of faint galaxies are subject to gravitational shearing followed by smearing with the…

Astrophysics · Physics 2009-10-31 Nick Kaiser

Estimating the actual head orientation from 2D images, with regard to its three degrees of freedom, is a well known problem that is highly significant for a large number of applications involving head pose knowledge. Consequently, this…

Computer Vision and Pattern Recognition · Computer Science 2020-03-26 Carmen Bisogni , Michele Nappi , Chiara Pero , Stefano Ricciardi

In turbid media, scattering of light scrambles information of the incident beam and represents an obstacle to optical imaging. Noninvasive imaging through opaque layers is challenging for dynamic and wide-field objects due to unreliable…

Optics · Physics 2018-10-17 Yuan Yuan , Hui Chen
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