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Related papers: WFPC2 aperture photometry and PSF modelling

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HSTphot, a photometry package designed to handle the undersampled PSFs found in WFPC2 images, is introduced and described, as well as some of the considerations that have to be made in order to obtain accurate PSF-fitting stellar photometry…

Astrophysics · Physics 2009-05-29 Andrew E. Dolphin

The knowledge of the exact structure of the optical system PSF enables a high-quality image reconstruction in fluorescence microscopy. Accurate PSF models account for the vector nature of light and the phase and amplitude modifications.…

We explore the impact of aperture size and shape on automotive camera systems for deep-learning-based tasks like traffic sign recognition and light state detection. A method is proposed to simulate optical effects using the point spread…

Computer Vision and Pattern Recognition · Computer Science 2025-01-17 Ofer Bar-Shalom , Tzvi Philipp , Eran Kishon

The limiting factor of the accuracy of WFPC2 photometry is the CTE loss, which has increased to the level of 50% or more for faint stars at the top of the chips. I describe recent work on characterizing this effect, and provide improved…

Astrophysics · Physics 2007-05-23 Andrew E. Dolphin

We present a theoretical analysis of the measuring algorithm we use when applying the Diffracto-Astrometry technique to Hubble Space Telescope Wide Field Planetary Camera 2 (WFPC2) saturated stellar images. Theoretical Point Spread…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 A. Ruelas-Mayorga , L. J. Sanchez , J. Olivares , C. Allen , A. Poveda , R. Costero , A. Nigoche-Netro

An undersampled point spread function may interact with the microstructure of a solid-state detector such that the total flux detected can depend sensitively on where the PSF center falls within a pixel. Such intra-pixel sensitivity…

Astrophysics · Physics 2009-10-31 Tod R. Lauer

Speckle photography can be used to monitor deformations of solid surfaces. The measuring characteristics, such as range or lateral resolution depend heavily on the optical recording and illumination set-up. This paper shows how, by the…

Optics · Physics 2014-01-30 Jose M. Diazdelacruz

We describe in this paper a new, public software for accurate "PSF-matched" multiband photometry for images of different resolution and depth, that we have named ConvPhot, of which we analyse performances and limitations. It is designed to…

Astrophysics · Physics 2009-11-13 C. De Santis , A. Grazian , A. Fontana , P. Santini

Charge-transfer effects in photometry with Wide Field Planetary Camera 2 aboard the Hubble Space Telescope are investigated by a comparison of WFPC2 observations with groundbased photometry for the Galactic globular clusters omega Centauri…

Astrophysics · Physics 2009-10-31 Peter B. Stetson

Validation of the quality of pansharpening methods is a difficult task because the reference is not directly available. In the meantime, two main approaches have been established: validation in reduced resolution and original resolution. In…

Computer Vision and Pattern Recognition · Computer Science 2021-11-16 Gintautas Palubinskas

Accurate astrometry and photometry of saturated and coronagraphic point spread functions (PSFs) are fundamental to both ground- and space-based high contrast imaging projects. For ground-based adaptive optics imaging, differential…

Astrophysics · Physics 2008-11-26 C. Marois , D. Lafreniere , B. Macintosh , R. Doyon

We present the photometric calibration of the HST Advanced Camera for Surveys (ACS). We give here an overview of the performance and calibration of the 2 CCD cameras, the Wide Field Channel (WFC) and the High Resolution Channel (HRC), and a…

Color-temperature relations and bolometric corrections in the HST-NICMOS F1110W, F160W and F222M and in the WFPC2 F439W, F555W and F814W photometric systems, using two different sets of model atmospheres, have been derived. This database of…

Astrophysics · Physics 2009-10-31 Livia Origlia , Claus Leitherer

Image distortion correction is a critical pre-processing step for a variety of computer vision and image processing algorithms. Standard real-time software implementations are generally not suited for direct hardware porting, so…

Computer Vision and Pattern Recognition · Computer Science 2016-11-01 Paolo Di Febbo , Stefano Mattoccia , Carlo Dal Mutto

The first step toward doing high-precision astrometry is the measurement of individual stars in individual images, a step that is fraught with dangers when the images are undersampled. The key to avoiding systematic positional error in…

Astrophysics · Physics 2009-10-05 Jay Anderson , Ivan R. King

Wide field planetary camera 2 (WFPC2) exposures are already some 20 years older than Gaia epoch observations, or future JWST observations. As such, they offer an unprecedented time baseline for high-precision proper-motion studies, provided…

Instrumentation and Methods for Astrophysics · Physics 2021-05-07 Dana I. Casetti-Dinescu , Terrence M. Girard , Vera Kozhurina-Platais , Imants Platais , Jay Anderson , Elliott P. Horch

In crowded fields, small-aperture photometry can reduce contamination errors from neighboring sources compared to larger aperture photometry. However, the UVIS encircled energy (EE) varies with detector position and focus variations on…

Instrumentation and Methods for Astrophysics · Physics 2025-10-28 K. Huynh , V. Bajaj , J. Mack , A. Calamida

This paper presents a method for carrying fair comparisons of the accuracy of pose estimation using fiducial markers. These comparisons rely on large sets of high-fidelity synthetic images enabling deep exploration of the 6 degrees of…

Computer Vision and Pattern Recognition · Computer Science 2026-01-13 Guillaume J. Laurent , Patrick Sandoz

Frontal photopolymerization (FPP) provides a versatile method for the rapid fabrication of solid polymer network materials by exposing photosensitive molecules to light. Dimensional control of structures created by this process is crucial…

Materials Science · Physics 2009-11-11 James A. Warren , Joao T. Cabral , Jack F. Douglas

We present a new method to derive reliable photometry of extended spherically symmetric sources from {\it HST} images (WFPC2, ACS/WFC and NICMOS/NIC2 cameras), extending existing studies of point sources and marginally resolved sources. We…

Astrophysics · Physics 2012-01-30 P. Anders , M. Gieles , R. de Grijs
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