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Related papers: High-Efficiency Lucky Imaging

200 papers

Fourier ptychography is a recently explored imaging method for overcoming the diffraction limit of conventional cameras with applications in microscopy and yielding high-resolution images. In order to splice together low-resolution images…

Image and Video Processing · Electrical Eng. & Systems 2020-03-18 Yican Chen , Zhi Luo , Xia Wu , Huidong Yang , Bo Huang

In this work, we propose using camera arrays coupled with coherent illumination as an effective method of improving spatial resolution in long distance images by a factor of ten and beyond. Recent advances in ptychography have demonstrated…

Computer Vision and Pattern Recognition · Computer Science 2015-11-29 Jason Holloway , M. Salman Asif , Manoj Kumar Sharma , Nathan Matsuda , Roarke Horstmeyer , Oliver Cossairt , Ashok Veeraraghavan

Accurate weak-lensing analysis requires not only accurate measurement of galaxy shapes but also precise and unbiased measurement of galaxy redshifts. The photometric redshift technique appears as the only possibility to determine the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 S. Jouvel , J-P. Kneib , G. Bernstein , O. Ilbert , P. Jelinsky , B. Milliard , A. Ealet , C. Schimd , T. Dahlen , S. Arnouts

Large ground-based telescopes equipped with adaptive optics (AO) systems have ushered in a new era of high-resolution infrared photometry and astrometry. Relative astrometric accuracies of <0.2 mas have already been demonstrated from…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Jessica R. Lu , Andrea M. Ghez , Sylvana Yelda , Tuan Do , Will Clarkson , Nate McCrady , Mark R. Morris

Optical interferometry has been successful at achieving milliarcsecond resolution on bright stars. Imaging performance can improve greatly by increasing the number of baselines, which has motivated proposals to build large (~ 100 m) optical…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Paul D. Nuñez , Antoine Labeyrie , Pierre Riaud

(Abridged) Weak gravitational lensing induces distortions on the images of background galaxies, and thus provides a direct measure of mass fluctuations in the universe. Since the distortions induced by lensing on the images of background…

Astrophysics · Physics 2009-10-31 David Bacon , Alexandre Refregier , Douglas Clowe , Richard Ellis

We present a method for speckle holography that is optimised for crowded fields. Its two key features are an iterativ improvement of the instantaneous Point Spread Functions (PSFs) extracted from each speckle frame and the (optional)…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 R. Schoedel , S. Yelda , A. Ghez , J. H. V. Girard , L. Labadie , R. Rebolo , A. Perez-Garrido , M. R. Morris

Large-format (sub)millimeter wavelength imaging arrays are best operated in scanning observing modes rather than traditional position-switched (chopped) modes. The choice of observing mode is critical for isolating source signals from…

Astrophysics · Physics 2014-11-18 A. Kovacs

A new algorithmic framework is presented for holographic phase retrieval via maximum likelihood optimization, which allows for practical and robust image reconstruction. This framework is especially well-suited for holographic coherent…

Image and Video Processing · Electrical Eng. & Systems 2022-02-18 David A. Barmherzig , Ju Sun

The statistical power of weak lensing measurements is principally driven by the number of high redshift galaxies whose shapes are resolved. Conventional wisdom and physical intuition suggest this is optimised by deep imaging at long (red or…

AstraLux is a Lucky Imaging camera for the Calar Alto 2.2-m telescope, based on an electron-multiplying high speed CCD. By selecting only the best 1-10% of several thousand short exposure frames, AstraLux provides nearly diffraction limited…

Astrophysics · Physics 2014-11-18 Felix Hormuth , Wolfgang Brandner , Stefan Hippler , Thomas Henning

Intelligent scheduling of the sequence of scientific exposures taken at ground-based astronomical observatories is massively challenging. Observing time is over-subscribed and atmospheric conditions are constantly changing. We propose to…

Instrumentation and Methods for Astrophysics · Physics 2020-11-09 Sankalp Gilda , Yuan-Sen Ting , Kanoa Withington , Matthew Wilson , Simon Prunet , William Mahoney , Sebastien Fabbro , Stark C. Draper , Andrew Sheinis

Optical turbulence modelling and simulation are crucial for developing astronomical ground-based instruments, laser communication, laser metrology, or any application where light propagates through a turbulent medium. In the context of…

Instrumentation and Methods for Astrophysics · Physics 2024-04-05 A. Berdja , M. Hadjara , M. Carbillet , R. L. Bernardi , R. G. Petrov

Large-scale astronomical surveys can capture numerous images of celestial objects, including galaxies and nebulae. Analysing and processing these images can reveal intricate internal structures of these objects, allowing researchers to…

Instrumentation and Methods for Astrophysics · Physics 2023-11-02 Peng Jia , Jiameng Lv , Runyu Ning , Yu Song , Nan Li , Kaifan Ji , Chenzhou Cui , Shanshan Li

We introduce a practical digital holographic method capable of imaging through a diffusive or scattering medium. The method relies on statistical averaging from a rotating ground glass diffuser to negate the adverse effects caused by…

AstraLux is the Lucky Imaging camera for the Calar Alto 2.2-m telescope, based on an electron-multiplying high speed CCD. By selecting only the best 1-10% of several thousand short exposure frames, AstraLux provides nearly diffraction…

Astrophysics · Physics 2009-11-13 Felix Hormuth , Stefan Hippler , Wolfgang Brandner , Karl Wagner , Thomas Henning

A long-held vision has been to realize diffraction-limited optical aperture synthesis over kilometer baselines. This will enable imaging of stellar surfaces and their environments, and reveal interacting gas flows in binary systems. An…

Instrumentation and Methods for Astrophysics · Physics 2015-08-12 Dainis Dravins , Tiphaine Lagadec , Paul D. Nuñez

The familiar tools of Fourier analysis and Fisher matrices are applied to derive the uncertainties on photometric, astrometric, and weak-lensing measurements of stars and galaxies in real astronomical images. Many effects or functions that…

Astrophysics · Physics 2007-05-23 Gary Bernstein

Spatial resolution of most imaging devices is fundamentally restricted by diffraction. This limitation is manifested in the loss of high spatial frequency information contained in evanescent waves. As a result, conventional far-field optics…

Optics · Physics 2010-03-16 Leonid Alekseyev , Evgenii Narimanov , Jacob Khurgin

GravityCam is a new concept of ground-based imaging instrument capable of delivering significantly sharper images from the ground than is normally possible without adaptive optics. Advances in optical and near infrared imaging technologies…