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A new method for improving the resolution of astronomical images is presented. It is based on the principle that sampled data cannot be fully deconvolved without violating the sampling theorem. Thus, the sampled image should not be…

Astrophysics · Physics 2009-10-30 P. Magain , F. Courbin , S. Sohy

A new concept of using focus-diverse point spread functions (PSFs) for modal wavefront sensing (WFS) is explored. This is based on relatively straightforward image moment analysis of measured PSFs, which differentiates it from other…

Optics · Physics 2012-02-27 Hanshin Lee

We explore the impact of aperture size and shape on automotive camera systems for deep-learning-based tasks like traffic sign recognition and light state detection. A method is proposed to simulate optical effects using the point spread…

Computer Vision and Pattern Recognition · Computer Science 2025-01-17 Ofer Bar-Shalom , Tzvi Philipp , Eran Kishon

First, we make a revision of the up-to-date Passive Scalar Fields properties: also, the refractive index is among them. Afterwards, we formulated the properties that make the family of `isotropic' fractional Brownian motion (with parameter…

Optics · Physics 2007-05-23 Dario G. Perez

We study the possibility of using quadrupole moments of auto-convolved galaxy images to measure cosmic shear. The autoconvolution of an image corresponds to the inverse Fourier transformation of its power spectrum. The new method has the…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-26 Xiangchong Li , Jun Zhang

Atmospheric turbulence, a common phenomenon in daily life, is primarily caused by the uneven heating of the Earth's surface. This phenomenon results in distorted and blurred acquired images or videos and can significantly impact downstream…

Computer Vision and Pattern Recognition · Computer Science 2024-02-13 Xijun Wang , Santiago López-Tapia , Aggelos K. Katsaggelos

Context: in astronomy, observing large fractions of the sky within a reasonable amount of time implies using large field-of-view (fov) optical instruments that typically have a spatially varying Point Spread Function (PSF). Depending on the…

Computer Vision and Pattern Recognition · Computer Science 2017-03-20 F. M. Ngolè Mboula , J. -L. Starck

We propose design of a low-cost passive scintillometer that measures the strength of optical turbulence by analyzing scintillation in the image of a straight edge between the two areas of uniform, but distinct brightness. Two theoretical…

Optics · Physics 2021-11-24 Mikhail Charnotskii

This study examines the influence of optical turbulence on field statistics using a nonlinear reconstruction and quantum phase-space formalism. Turbulence-distorted intensity sequences were processed through a nonlinear P3-type partial…

Optics · Physics 2025-10-27 Shouvik Sadhukhan , C. S. Narayanamurthy

We present a detailed analysis of the point spread function (PSF) of JWST NIRCam imaging in eight filters: F070W, F115W, F150W, F200W, F277W, F356W, F444W, and F480M, using publicly available data. Spatial variations in the PSF FWHM…

Astrophysics of Galaxies · Physics 2023-04-28 Ming-Yang Zhuang , Yue Shen

In this paper we present the approach we have used to determine and account for the anisoplanatic point spread function (PSF) in deep adaptive optics (AO) images for the Survey of a Wide Area with NACO (SWAN) at the ESO VLT. The survey…

Astrophysics · Physics 2009-11-11 G. Cresci , R. I. Davies , A. J. Baker , M. D. Lehnert

Shape from Polarization (SfP) estimates surface normals using photos captured at different polarizer rotations. Fundamentally, the SfP model assumes that light is reflected either diffusely or specularly. However, this model is not valid…

Computer Vision and Pattern Recognition · Computer Science 2016-06-14 Vage Taamazyan , Achuta Kadambi , Ramesh Raskar

In this second paper in a series dedicated to developing efficient numerical techniques for the deblurring Cosmic Microwave Background (CMB) maps, we consider the case of asymmetric point spread functions (PSF). Although conceptually this…

Astrophysics · Physics 2009-11-10 R. Vio , J. G. Nagy , L. Tenorio , P. Andreani , C. Baccigalupi , W. Wamsteker

The spatial resolution of astronomical images is limited by atmospheric turbulence and diffraction in the telescope optics, resulting in blurred images. This makes it difficult to accurately measure the brightness of blended objects because…

Instrumentation and Methods for Astrophysics · Physics 2023-05-31 Kevin Michalewicz , Martin Millon , Frédéric Dux , Frédéric Courbin

We derive general properties of anomalous diffusion and nonexponential relaxation from the theory of tempered \alpha-stable processes. Its most important application is to overcome the infinite-moment difficulty for the \alpha-stable random…

Statistical Mechanics · Physics 2011-11-15 Aleksander Stanislavsky , Karina Weron , Aleksander Weron

Blur in X-ray radiographs not only reduces the sharpness of image edges but also reduces the overall contrast. The effective blur in a radiograph is the combined effect of blur from multiple sources such as the detector panel, X-ray source…

Image and Video Processing · Electrical Eng. & Systems 2020-09-08 K. Aditya Mohan , Robert M. Panas , Jefferson A. Cuadra

A major issue in optical astronomical image analysis is the combined effect of the instrument's point spread function (PSF) and the atmospheric seeing that blurs images and changes their shape in a way that is band and time-of-observation…

Instrumentation and Methods for Astrophysics · Physics 2024-10-02 Sreevarsha Sreejith , Anže Slosar , Hong Wang

We outline a technique called Dual Plane Imaging which should significantly improve images which would otherwise be blurred due to atmospheric turbulence. The technique involves capturing all the spatial, directional and temporal…

Instrumentation and Methods for Astrophysics · Physics 2015-01-29 Ian Parry , Anna Moore

The ability to accurately measure the shapes of faint objects in images taken with the Advanced Camera for Surveys(ACS) on the Hubble Space Telescope (HST) depends upon detailed knowledge of the Point Spread Function (PSF). We show that…

The Probability Distribution Function of plasma density fluctuations at the edge of fusion devices is known to be skewed and strongly non-Gaussian. The causes of this peculiar behaviour are, up to now, largely unexplored. On the other hand,…

Plasma Physics · Physics 2007-05-23 F. Sattin , N. Vianello
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