CenterAndProfile#

class stellarphot.photometry.profiles.CenterAndProfile(data, center_approx, centering_cutout_size=30, profile_radius=None, max_iters=10, match_limit=3)[source]#

Bases: object

Class to determine center of and hold radial profile information for a star.

Parameters:

dataastropy.nddata.CCDData or numpy array: Image data
center_approxlist-like: x, y position of the center in pixel coordinates, i.e. horizontal coordinate then vertical.
cutout_sizeint, optional: Width of the rectangular image cutout to use in looking for a star.
profile_radiusint, optional: Maximum radius to use in constructing the profile.
max_itersint, optional: Maximum number of iterations to go through in finding the center.
match_limitint, optional: Maximum number of pixels to allow the COM centroid and Gaussian center to differ.

Attributes Summary

`FWHM`	Full-width half-max of the radial profile.
`HWHM`	Half-width half-max of the radial profile.
`center`	x, y position of the center of the star.
`curve_of_growth`	Curve of growth for the star.
`cutout_center`
`max_iters`	Maximum number of iterations to go through in finding the center.
`normalized_profile`	Radial profile scaled to have a maximum of 1.
`pixel_values_in_profile`	Pixel values in the radial profile.
`profile_cutout`	Cutout image around the star.
`radial_profile`	Radial profile of the star.
`sky_area`	Area of the sky annulus.
`sky_pixel_value`	Pixel values for the sky, i.e. more than 3 FWHM from the star.

Methods Summary

`noise`(camera, exposure)	Noise in the star.
`snr`(camera, exposure)	Signal to noise ratio of the star.

Attributes Documentation

FWHM#: Full-width half-max of the radial profile.

HWHM#: Half-width half-max of the radial profile.

center#: x, y position of the center of the star.

curve_of_growth#: Curve of growth for the star.

cutout_center#

max_iters#: Maximum number of iterations to go through in finding the center.

normalized_profile#: Radial profile scaled to have a maximum of 1.

pixel_values_in_profile#: Pixel values in the radial profile.

profile_cutout#: Cutout image around the star.

radial_profile#: Radial profile of the star.

sky_area#: Area of the sky annulus.

sky_pixel_value#: Pixel values for the sky, i.e. more than 3 FWHM from the star.

Methods Documentation

noise(camera, exposure)[source]#

Noise in the star.

Parameters:

camerastellarphot.settings.Camera: Camera settings.
exposurefloat: Exposure time in seconds.

Returns:

noisenumpy.ndarray of float: Noise calculated using the CCD equation.

snr(camera, exposure)[source]#

Signal to noise ratio of the star.

Parameters:

camerastellarphot.settings.Camera: Camera settings.
exposurefloat: Exposure time in seconds.

Returns:

snrnumpy.ndarray of float: Signal to noise ratio.