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Related papers: WFPC2 aperture photometry and PSF modelling

200 papers

High-fidelity simulated astronomical images are an important tool in developing and measuring the performance of image-processing algorithms, particularly for high precision measurements of cosmic shear -- correlated distortions of images…

Instrumentation and Methods for Astrophysics · Physics 2024-03-25 Claire-Alice Hébert , Joshua E. Meyers , My H. Do , Patricia R. Burchat , the LSST Dark Energy Science Collaboration

Numerical simulation of Fresnel diffraction with fast Fourier transform (FFT) is widely used in optics, especially computer holography. Fresnel diffraction with FFT cannot set different sampling rates between source and destination planes,…

The modulation transfer function (MTF) is widely used to characterise the performance of optical systems. Measuring it is costly and it is thus rarely available for a given lens specimen. Instead, MTFs based on simulations or, at best, MTFs…

Computer Vision and Pattern Recognition · Computer Science 2018-05-07 Matthias Bauer , Valentin Volchkov , Michael Hirsch , Bernhard Schölkopf

In single molecule orientation localization microscopy, valuable information about the orientation and longitudinal position of each molecule is often encoded in the shape of the point spread function (PSF). This shape, though, can be…

Wide field-of-view (FOV) cameras, which capture a larger scene area than narrow FOV cameras, are used in many applications including 3D reconstruction, autonomous driving, and video surveillance. However, wide-angle images contain…

Computer Vision and Pattern Recognition · Computer Science 2021-12-02 Jinlong Fan , Jing Zhang , Stephen J. Maybank , Dacheng Tao

The photometric stereo (PS) problem consists in reconstructing the 3D-surface of an object, thanks to a set of photographs taken under different lighting directions. In this paper, we propose a multi-scale architecture for PS which,…

Computer Vision and Pattern Recognition · Computer Science 2023-10-05 Clément Hardy , Yvain Quéau , David Tschumperlé

The point-spread function (PSF) of an imaging system describes the response of the system to a point source. Accurately determining the PSF enables one to correct for the combined effects of focussing and scattering within the imaging…

Instrumentation and Methods for Astrophysics · Physics 2022-11-01 Stefan Johann Hofmeister , Michael Hahn , Daniel Wolf Savin

We present an algorithm for performing precise aperture photometry on critically sampled astrophysical images. The method is intended to overcome the small-aperture limitations imposed by point-sampling. Aperture fluxes are numerically…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Steven Bickerton , Robert Lupton

The use of individual multimode optical fibers in endoscopy applications has the potential to provide highly miniaturized and noninvasive probes for microscopy and optical micromanipulation. A few different strategies have been proposed…

We present a novel, easy-to-use method based on the photon-mapping technique to simulate photometric images of moving targets. Realistic images can be created in two passes: photon tracing and image rendering. The nature of light sources,…

Instrumentation and Methods for Astrophysics · Physics 2021-10-13 Junju Du , Shaoming Hu , Xu Chen , Hai Cao , Yuchen Jiang

The weak-lensing science of the LSST project drives the need to carefully model and separate the instrumental artifacts from the intrinsic lensing signal. The dominant source of the systematics for all ground based telescopes is the spatial…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 M. James Jee , J. Anthony Tyson

This Point spread function (PSF) plays a crucial role in many computational imaging applications, such as shape from focus/defocus, depth estimation, and fluorescence microscopy. However, the mathematical model of the defocus process is…

Computer Vision and Pattern Recognition · Computer Science 2022-09-20 Renzhi He , Yan Zhuang , Boya Fu , Fei Liu

There is widespread interest in estimating the fluorescence properties of natural materials in an image. However, the separation between reflected and fluoresced components is difficult, because it is impossible to distinguish reflected and…

Computer Vision and Pattern Recognition · Computer Science 2016-05-16 Henryk Blasinski , Joyce Farrell , Brian Wandell

In point spread function (PSF) photometry, the selection of the fitting aperture radius plays a critical role in determining the precision of flux and background estimations. Traditional methods often rely on maximizing the signal-to-noise…

Instrumentation and Methods for Astrophysics · Physics 2025-10-08 Sebastian Espinosa , Mario L. Vicuña , Rene A. Mendez , Jorge F. Silva , Marcos Orchard

Ultrasound imaging often suffers from image degradation stemming from phase aberration, which represents a significant contributing factor to the overall image degradation in ultrasound imaging. Frequency-space prediction filtering or FXPF…

Image and Video Processing · Electrical Eng. & Systems 2023-08-24 Mostafa Sharifzadeh , Habib Benali , Hassan Rivaz

The technique requires the epipolar geometry to be pre-estimated between each image pair. It exploits the constraints which the camera movement implies, in order to apply a closed-form correction to the parameters of the input affinities.…

Computer Vision and Pattern Recognition · Computer Science 2019-05-03 Ivan Eichhardt , Daniel Barath

We investigate the ellipticity of the point-spread function (PSF) produced by imaging an unresolved source with a telescope, subject to the effects of atmospheric turbulence. It is important to quantify these effects in order to understand…

Astrophysics · Physics 2011-02-11 W. H. de Vries , S. S. Olivier , S. J. Asztalos , L. J. Rosenberg , K. L. Baker

Reconstruction of the point spread function (PSF) is a critical process in weak lensing measurement. We develop a real-data based and galaxy-oriented pipeline to compare the performances of various PSF reconstruction schemes. Making use of…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-24 Tianhuan Lu , Jun Zhang , Fuyu Dong , Yingke Li , Dezi Liu , Liping Fu , Guoliang Li , Zuhui Fan

We examined the anisotropic point spread function (PSF) of Suprime-Cam data utilizing dense star field data. We decomposed the PSF ellipticities into three components, the optical aberration, atmospheric turbulence, and chip-misalignment in…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Takashi Hamana , Satoshi Miyazaki , Yuki Okura , Tomohiro Okamura , Toshifumi Futamase

Fine-tuning pre-trained foundation models has gained significant popularity in various research fields. Existing methods for fine-tuning can be roughly divided into two categories, namely Parameter-Efficient Fine-Tuning and High-Performance…

Computer Vision and Pattern Recognition · Computer Science 2023-12-27 Peng Ye , Yongqi Huang , Chongjun Tu , Minglei Li , Tao Chen , Tong He , Wanli Ouyang