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Related papers: WFPC2 aperture photometry and PSF modelling

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A critical analysis and comparison of different methods for obtaining point spread function (PSF) photometry are carried out. Deep ACS observations of NGC3370 were reduced using four distinct approaches. These reductions explore a number of…

Astrophysics of Galaxies · Physics 2023-03-08 In Sung Jang

Given the basic parameters of a cosmic shear weak lensing survey, how well can systematic errors due to anisotropy in the point spread function (PSF) be corrected? The largest source of error in this correction to date has been the…

Astrophysics · Physics 2009-11-13 Bhuvnesh Jain , Mike Jarvis , Gary Bernstein

Optimal error estimation is key to achieve accurate photometry and astrometry. Stellar fluxes and positions in high angular resolution images are typically measured with PSF fitting routines, such as StarFinder. However, the formal…

Instrumentation and Methods for Astrophysics · Physics 2022-08-12 E. Gallego-Cano , R. Schödel , A. T. Gallego-Calvente , A. M. Ghez

Photon coincidence spectroscopy is a promising technique for probing the nonlinear regime of cavity quantum electrodynamics in the optical domain, however its accuracy is mitigated by two factors: higher-order photon correlations, which…

Quantum Physics · Physics 2009-09-25 L. Horvath , B. C. Sanders

Kepler and K2 data analysis reported in the literature is mostly based on aperture photometry. Because of Kepler's large, undersampled pixels and the presence of nearby sources, aperture photometry is not always the ideal way to obtain…

Solar and Stellar Astrophysics · Physics 2016-01-27 M. Libralato , L. R. Bedin , D. Nardiello , G. Piotto

In two-dimensional spectrographs, the optical distortions in the spatial and dispersion directions produce variations in the sub-pixel sampling of the background spectrum. Using knowledge of the camera distortions and the curvature of the…

Astrophysics · Physics 2009-12-08 Daniel D. Kelson

Knowledge of the atmospheric turbulence in the telescope line-of-sight is crucial for wide-field observations assisted by adaptive optics (AO), for which the Point Spread Function (PSF) becomes strongly elongated due to the anisoplanatism…

Instrumentation and Methods for Astrophysics · Physics 2018-09-26 O. Beltramo-Martin , C. M. Correia , B. Neichel , T. Fusco

We introduce a new algorithm for interpolating measurements of the point-spread function (PSF) using stars from many exposures. The principal components of the variation in the PSF pattern from multiple exposures are used to solve for…

Astrophysics · Physics 2007-05-23 Mike Jarvis , Bhuvnesh Jain

We introduce a novel framework for upsampled Point Spread Function (PSF) modeling using pixel-level Bayesian inference. Accurate PSF characterization is critical for precision measurements in many fields including: weak lensing, astrometry,…

Instrumentation and Methods for Astrophysics · Physics 2025-11-26 Connor Stone , Ronan Legin , Alexandre Adam , Nikolay Malkin , Gabriel Missael Barco , Laurence Perreaul-Levasseur , Yashar Hezaveh

Accurate modelling of the effective point spread function (ePSF) is essential for high-precision photometry and astrometry, particularly in undersampled imaging regimes. In this work, we build on a well-established ePSF modelling framework…

Instrumentation and Methods for Astrophysics · Physics 2025-12-19 Emma Godden , Katherine M. Blundell

A simple theoretical framework for the description and interpretation of spatially correlated modelling residuals is presented, and the resulting tools are found to provide a useful aid to model selection in the context of weak…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 Barnaby Rowe

One of the possible approaches to detecting optical counterparts of GRBs requires monitoring large parts of the sky. This idea has gained some instrumental support in recent years, such as with the "Pi of the Sky" project. The broad sky…

Fourier ptychography (FP) is a powerful light-based synthetic aperture imaging technique that allows one to reconstruct a high-resolution, wide field-of-view image by computationally integrating a diverse collection of low-resolution,…

Image and Video Processing · Electrical Eng. & Systems 2025-07-21 Matthew A. Chan , Casey J. Pellizzari , Christopher A. Metzler

Charge-transfer loss on the Wide Field Planetary Camera 2 (WFPC2) onboard the Hubble Space Telescope is a primary source of uncertainty in stellar photometry obtained with this camera. This effect, discovered shortly after the camera was…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Andrew E. Dolphin

Matching two images while estimating their relative geometry is a key step in many computer vision applications. For decades, a well-established pipeline, consisting of SIFT, RANSAC, and 8-point algorithm, has been used for this task.…

Computer Vision and Pattern Recognition · Computer Science 2019-09-13 Jia-Wang Bian , Yu-Huan Wu , Ji Zhao , Yun Liu , Le Zhang , Ming-Ming Cheng , Ian Reid

This article describes the various photometric techniques currently being used, including some preliminary results from the large CNOC2 redshift survey. It also presents a critical look at the reliability of the photometric redshift…

Astrophysics · Physics 2007-05-23 H. K. C. Yee

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

Weak gravitational lensing is one of the most powerful tools for cosmology, while subject to challenges in quantifying subtle systematic biases. The Point Spread Function (PSF) can cause biases in weak lensing shear inference when the PSF…

Instrumentation and Methods for Astrophysics · Physics 2021-12-13 Tianqing Zhang , Rachel Mandelbaum , The LSST Dark Energy Science Collaboration

Photometric stereo, a problem of recovering 3D surface normals using images of an object captured under different lightings, has been of great interest and importance in computer vision research. Despite the success of existing traditional…

Computer Vision and Pattern Recognition · Computer Science 2022-08-31 Ashish Tiwari , Shanmuganathan Raman

Reducing the aperture size is a conventional technique to obtain enhanced image resolution in optics but it is obscured by depleting illumination. Polarization coded apertures (PCAs) can be employed to circumvent this critical artifact. We…

Optics · Physics 2022-04-11 Vipin Tiwari , Nandan S. Bisht