English
Related papers

Related papers: WFPC2 aperture photometry and PSF modelling

200 papers

We present a novel method to correct flying pixels within data captured by Time-of-flight (ToF) sensors. Flying pixel (FP) artifacts occur when signals from foreground and background objects reach the same sensor pixel, leading to a…

Image and Video Processing · Electrical Eng. & Systems 2024-10-11 Ekamresh Vasudevan , Shashank N. Sridhara , Eduardo Pavez , Antonio Ortega , Raghavendra Singh , Srinath Kalluri

Following the recent developement of Fourier ptychographic microscopy (FPM) in the visible range by Zheng et al. (2013), we propose an adaptation for hard x-rays. FPM employs ptychographic reconstruction to merge a series of low-resolution,…

Instrumentation and Detectors · Physics 2016-09-27 H. Simons , H. F. Poulsen , J. P. Guigay , C. Detlefs

Motivated by the recognition that variation in the optical transmission of the atmosphere is probably the main limitation to the precision of ground-based CCD measurements of celestial fluxes, we review the physical processes that attenuate…

All optical systems, which involve the collimation of a reflected, transmitted or scattered wave subsequent to tight focusing, are subject to two kinds of deviations. One is the wavefront curvature due to inaccurate focal placement of the…

Optics · Physics 2024-06-10 Nitish Kumar , Anirban Debnath , Nirmal K. Viswanathan

Image feature matching plays a vital role in many computer vision tasks. Although many image feature detection and matching techniques have been proposed over the past few decades, it is still time-consuming to match feature points in two…

Computer Vision and Pattern Recognition · Computer Science 2025-10-14 Chin-Hung Teng , Ben-Jian Dong

Due to limited size and imperfect of the optical components in a spectrometer, aberration has inevitably been brought into two-dimensional multi-fiber spectrum image in LAMOST, which leads to obvious spacial variation of the point spread…

Instrumentation and Methods for Astrophysics · Physics 2020-10-28 Jiali Xu , Qian Yin , Ping Guo , Xin Zheng

We investigate methods to calibrate the non-common path aberrations at an adaptive optics system having a wavefront-correcting device working at an extremely high resolution (larger than 150x150). We use focal-plane images collected…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Visa Korkiakoski , Christoph U. Keller , Niek Doelman , Matthew Kenworthy , Gilles Otten , Michel Verhaegen

We present PyGFit, a program designed to measure PSF-matched photometry from images with disparate pixel scales and PSF sizes. While PyGFit has a number of uses, its primary purpose is to extract robust spectral energy distributions (SEDs)…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Conor L. Mancone , Anthony H. Gonzalez , Leonidas A. Moustakas , Andrew Price

Estimating relative camera poses between images has been a central problem in computer vision. Methods that find correspondences and solve for the fundamental matrix offer high precision in most cases. Conversely, methods predicting pose…

Computer Vision and Pattern Recognition · Computer Science 2024-03-06 Chris Rockwell , Nilesh Kulkarni , Linyi Jin , Jeong Joon Park , Justin Johnson , David F. Fouhey

Context. Adaptive optics (AO) is now a tool commonly deployed in astronomy. The real time correction of the atmospheric turbulence that AO enables allows telescopes to perform close to the diffraction limit at the core of their point spread…

Instrumentation and Methods for Astrophysics · Physics 2023-06-21 Anthony Berdeu , Michel Tallon , Éric Thiébaut , Maud Langlois

Smartphone cameras today are increasingly approaching the versatility and quality of professional cameras through a combination of hardware and software advancements. However, fixed aperture remains a key limitation, preventing users from…

Computer Vision and Pattern Recognition · Computer Science 2023-04-07 Hadi Alzayer , Abdullah Abuolaim , Leung Chun Chan , Yang Yang , Ying Chen Lou , Jia-Bin Huang , Abhishek Kar

We directly observe far-field correlations of x-ray photon pairs generated by spontaneous parametric down-conversion (SPDC). Using an energy-resolved, two-dimensional photon counting detector we record the full ring-shaped emission of both…

A new model-based image adjustment for the enhancement of multi-resolution image fusion or pansharpening is proposed. Such image adjustment is needed for most pansharpening methods using panchromatic band and/or intensity image (calculated…

Image and Video Processing · Electrical Eng. & Systems 2021-03-05 Gintautas Palubinskas

Despite the high accuracy of photometric redshifts (zphot) derived using Machine Learning (ML) methods, the quantification of errors through reliable and accurate Probability Density Functions (PDFs) is still an open problem. First, because…

We present a novel automatic adaptive aperture photometry algorithm for measuring the total magnitudes of merging galaxies with irregular shapes. First, we use a morphological pattern recognition routine for identifying the shape of an…

Instrumentation and Methods for Astrophysics · Physics 2017-02-08 Jen-Chao Huang , Chorng-Yuan Hwang

Fourier ptychography (FP) is a recently proposed computational imaging technique for high space-bandwidth product imaging. In real setups such as endoscope and transmission electron microscope, the common sample motion largely degrades the…

We study the morphology of convergence maps by perturbatively reconstructing their Minkowski Functionals (MFs). We present a systematics study using a set of three generalised skew-spectra as a function of source redshift and smoothing…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-01 D. Munshi , T. Namikawa , J. D. McEwen , T. D. Kitching , F. R. Bouchet

This paper presents an integrated modeling software to analyze the PSF of wide-field telescopes affected by misalignments. Even relatively small misalignments in the optical system of a telescope can significantly deteriorate the image…

Instrumentation and Methods for Astrophysics · Physics 2021-12-14 Salvatore Savarese , Pietro Schipani , Giulio Capasso , Mirko Colapietro , Sergio D'Orsi , Marcella Iuzzolino , Laurent Marty , Francesco Perrotta , Giacomo Basile

The point spread function (PSF) is fundamental to any type of microscopy, most importantly so for single-molecule localization techniques, where the exact PSF shape is crucial for precise molecule localization at the nanoscale. However,…

Pansharpening aims at fusing a panchromatic image with a multispectral one, to generate an image with the high spatial resolution of the former and the high spectral resolution of the latter. In the last decade, many algorithms have been…

‹ Prev 1 8 9 10 Next ›