ObsVIS Class Reference

It creates a realistic image from the output of a ray-tracing simulation. More...

#include <image_processing.h>

Public Member Functions
	ObsVIS (size_t Npix_x, size_t Npix_y, int oversample, double resolution=0.1 *arcsecTOradians)
	exposure times are set to wide survey expectations
	ObsVIS (size_t Npix_x, size_t Npix_y, const std::vector< double > &exposure_times, int oversample)
	background set to 0.0015 and 0.1'' pixels
	ObsVIS (size_t Npix_x, size_t Npix_y, const std::vector< double > &exposure_times, int oversample, double resolution, double background_sigma, double calibration_exposure_time)
template<typename T >
void	AddPoisson (PixelMap< T > &pmap, Utilities::RandomNumbers_NR &ran)
	add poisson noise to an image that is in units of electrons
template<typename T >
void	AddNoise (PixelMap< T > &pmap, PixelMap< T > &error_map, Utilities::RandomNumbers_NR &ran, bool cosmic=true)
	Applies noise (read-out + Poisson) on an image, returns noise map.
template<typename T >
void	Convert (PixelMap< T > &map_in, PixelMap< T > &map_out, PixelMap< T > &error_map, bool psf, bool noise, Utilities::RandomNumbers_NR &ran, bool cosmic=false)
double	mag_to_counts (double m) const
double	counts_to_mag (double flux) const
double	zeropoint () const
void	setZeropoint (double zpoint)
float	getBackgroundNoise () const
	returns std of pixels in e-

Detailed Description

It creates a realistic image from the output of a ray-tracing simulation.

It translates pixel values in observed units (counts/sec), applies PSF and noise. Input must be in ergs/(s*cm^2*Hz).

The oversample parameter is the ratio between the pixel size of the input image to the output image. The input image must have the same resolution as the PSF so oversample is slao the oversampling of the PSF.

see https://www.ucolick.org/~bolte/AY257/s_n.pdf

Constructor & Destructor Documentation

ObsVIS() [1/3]

ObsVIS::ObsVIS	(	size_t	Npix_x,
		size_t	Npix_y,
		int	oversample,
		double	resolution = 0.1*arcsecTOradians )

exposure times are set to wide survey expectations

Parameters

Npix_x	number of pixels in final observation
Npix_y	number of pixels in final observation
oversample	oversampling factor for input image, >= 1
resolution	pixel size in radians

ObsVIS() [2/3]

ObsVIS::ObsVIS	(	size_t	Npix_x,
		size_t	Npix_y,
		const std::vector< double > &	exposure_times,
		int	oversample )

background set to 0.0015 and 0.1'' pixels

Parameters

Npix_x	number of pixels in final observation
Npix_y	number of pixels in final observation
exposure_times	in seconds for each dither
oversample	oversampling factor for input image, >= 1

ObsVIS() [3/3]

ObsVIS::ObsVIS	(	size_t	Npix_x,
		size_t	Npix_y,
		const std::vector< double > &	exposure_times,
		int	oversample,
		double	resolution,
		double	background_sigma,
		double	calibration_exposure_time )

Parameters

Npix_x	number of pixels in final observation
Npix_y	number of pixels in final observation
exposure_times	in seconds for each dither
oversample	oversampling factor for input image, >= 1
resolution	pixel size in radians
background_sigma	background rms in output units
calibration_exposure_time	the exposure time corresponding to background_sigma

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The documentation for this class was generated from the following files:

• SLsimLib/include/image_processing.h
• SLsimLib/ImageProcessing/observation.cpp