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Related papers: Peak-locking centroid bias in Shack-Hartmann wavef…

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We present an experimental test of the use of stress engineered optics incorporated into a Shack-Hartmann wavefront sensor in such a way that the shape of the point spread function (PSF) provides polarization information while the…

Instrumentation and Detectors · Physics 2026-03-17 David E. Spiecker , Thomas G. Brown

Capturing photographs with wrong exposures remains a major source of errors in camera-based imaging. Exposure problems are categorized as either: (i) overexposed, where the camera exposure was too long, resulting in bright and washed-out…

Image and Video Processing · Electrical Eng. & Systems 2021-03-31 Mahmoud Afifi , Konstantinos G. Derpanis , Björn Ommer , Michael S. Brown

We investigate the focal plane wavefront sensing technique, known as Phase Diversity, at the scientific focal plane of a segmented mirror telescope with an adaptive optics (AO) system. We specifically consider an optical system imaging a…

Instrumentation and Methods for Astrophysics · Physics 2021-05-03 Masen Lamb , Carlos Correia , Suresh Sivanandam , Robin Swanson , Polina Zavyalova

Camera calibration using planar targets has been widely favored, and two types of control points have been mainly considered as measurements: the corners of the checkerboard and the centroid of circles. Since a centroid is derived from…

Computer Vision and Pattern Recognition · Computer Science 2025-12-16 Chaehyeon Song , Dongjae Lee , Jongwoo Lim , Ayoung Kim

The performance of adaptive optics systems is partially dependant on the algorithms used within the real-time control system to compute wavefront slope measurements. We demonstrate use of a matched filter algorithm for the processing of…

We present a method of centroiding undersampled point spread functions (PSFs) that may be useful, especially when dithering is not an option. If the profile of the expected PSF is known fairly well through characterization of the telescope…

Instrumentation and Methods for Astrophysics · Physics 2025-03-05 Kevin J. Ludwick , Ashley Mazingo

Stacking analysis is a means of detecting faint sources using a priori position information to estimate an aggregate signal from individually undetected objects. Confusion severely limits the effectiveness of stacking in deep surveys with…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Peter Kurczynski , Eric Gawiser

Due to their affordable, low mass, and small dimensions, uncooled microbolometer-based thermal focal plane arrays (UC-FPAs) are useful for long-wave infrared (LWIR)imaging applications. However, in outdoor conditions typical in agricultural…

Image and Video Processing · Electrical Eng. & Systems 2025-03-05 Peretz Yafin , Nir Sochen , Iftach Klapp

Measuring the centroid of a spectral line is a common problem in astronomy. Many methods have been devised to overcome limitations due to either noise in the spectra or asymmetric profiles, the most common of which are the intensity…

Instrumentation and Methods for Astrophysics · Physics 2018-09-28 Richard Teague , Daniel Foreman-Mackey

In this article we compare the cross-correlation and breakfinder techniques applied to the measurements of redshifts from low-resolution spectra. We assume spectra obtained from multinarrowband imagery, a technique for multi-object…

Astrophysics · Physics 2009-10-28 R. Cabanac , E. F. Borra

Corner detection is a vital operation in numerous computer vision applications. The Chord-to-Point Distance Accumulation (CPDA) detector is recognized as the contour-based corner detector producing the lowest localization error while…

Computer Vision and Pattern Recognition · Computer Science 2017-08-22 Mohammad Asiful Hossain , Abdul Kawsar Tushar , Shofiullah Babor

We present a new method employing machine learning techniques for measuring astrophysical features by correcting systematics in IRAC high precision photometry using Random Forests. The main systematic in IRAC light curve data is position…

Instrumentation and Methods for Astrophysics · Physics 2020-08-12 Jessica Krick , Jonathan Fraine , Jim Ingalls , Sinan Deger

Context. Solar wavefront sensing has been a challenge for astrophysical instrumentalists, due to the low contrast between the Sun and the sky background compared to night-time observations, which limits the performance of adaptive optics…

X-ray photon-counting detectors (PCDs) are drawing an increasing attention in recent years due to their low noise and energy discrimination capabilities. The energy/spectral dimension associated with PCDs potentially brings great benefits…

Medical Physics · Physics 2020-07-08 Mengzhou Li , David S. Rundle , Ge Wang

The proposed system outlined in this paper is a solution to a use case that requires the autonomous picking of cuboidal objects from an organized or unorganized pile with high precision. This paper presents an efficient method for precise…

Computer Vision and Pattern Recognition · Computer Science 2025-05-09 Utsav Rai , Hardik Mehta , Vismay Vakharia , Aditya Choudhary , Amit Parmar , Rolif Lima , Kaushik Das

In adaptive optics, the tracker and wavefront sensor commonly measure irradiance centroids (in their respective focal planes) to estimate the turbulence-degraded wavefront in the pupil plane. Several factors affect the accuracy of these…

Optics · Physics 2025-05-02 Milo W. Hyde , Eric W. Mitchell , Mark F. Spencer

We extensively compare, qualitatively and quantitatively, 40 state-of-the-art models (28 salient object detection, 10 fixation prediction, 1 objectness, and 1 baseline) over 6 challenging datasets for the purpose of benchmarking salient…

Computer Vision and Pattern Recognition · Computer Science 2018-03-02 Ali Borji , Ming-Ming Cheng , Huaizu Jiang , Jia Li

A pupil plane wavefront reconstruction procedure is proposed based on analysis of a sequence of focal plane images corresponding to a sequence of random pupil plane phase probes. The developed method provides the unique nontrivial solution…

Instrumentation and Methods for Astrophysics · Physics 2018-11-13 Eugene Pluzhnik , Dan Sirbu , Ruslan Belikov , Eduardo Bendek , Vladimir N. Dudinov

We derive fundamental accuracy limits for distributed localization when a fusion center has access only to independently rate-distortion (RD)-optimally compressed versions of multi-sensor observations, under a line-of-sight propagation…

Information Theory · Computer Science 2026-03-31 Amir Weiss

Conventional LIDAR systems require hundreds or thousands of photon detections to form accurate depth and reflectivity images. Recent photon-efficient computational imaging methods are remarkably effective with only 1.0 to 3.0 detected…

Applications · Statistics 2019-11-13 Joshua Rapp , Vivek K Goyal
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