Exemplo n.º 1
0
    def __init__(self, filename, distance):

        fits = pyfits.open(filename)
        # compress all images into one image by average all the pixels
        if len(fits[0].data.shape) == 3:
            print("Found {0} exposures. Averaging...".format(
                fits[0].data.shape[0]))
            data = np.average(fits[0].data, axis=0)
        else:
            data = fits[0].data

        # create the wcs information
        w = WCS(naxis=2)
        w.wcs.crpix = [0, 0]
        plate_scale = foxsi_optics_calib.plate_scale(distance).to('arcsec')
        w.wcs.cdelt = plate_scale.value * np.ones(2)
        w.wcs.crval = [0, 0]
        w.wcs.ctype = ["TAN", "TAN"]
        CCDData.__init__(self, data, wcs=w, unit='adu',
                         header=deepcopy(fits[0].header))
        # save the name of the filename
        self.filename = os.path.basename(filename)

        x, y = np.meshgrid(*[np.arange(v) for v in self.data.shape]) * u.pixel
        self.xaxis, self.yaxis = self.wcs.wcs_pix2world(x, y, 1) * u.arcsec
        self.xlim = np.floor(
            [np.min(self.xaxis).value, np.max(self.xaxis).value])
        self.ylim = np.floor(
            [np.min(self.yaxis).value, np.max(self.yaxis).value])
Exemplo n.º 2
0
 def __init__(self, filename, pinhole_size=0.05 * u.mm):
     xy = []
     spectra = []
     self.energy_axis = (ENERGY_CALIB_M *
                         (np.arange(0, NUMBER_OF_CHANNELS) + 1) -
                         ENERGY_CALIB_B) * u.keV
     self.filename = filename
     self.position, self.data = self._parse_file(filename)
     self.pinhole_size = pinhole_size
     self.plate_scale = foxsi_optics_calib.plate_scale(1 * u.mm)
     self.error = np.sqrt(self.data.value) * u.count
     # recenter based on max position
     total_counts = np.sum(self.data, axis=1)
     max_position = self.position[np.argmax(total_counts), 1]
     self.position[:, 1] = self.position[:, 1] - max_position
     self._fit()
Exemplo n.º 3
0
 def plot_scan(self, energy_range=None, ax=None):
     if not ax:
         ax = plt.subplot()
     total_counts = np.sum(self.data, axis=1)
     err_counts = np.sqrt(total_counts.value) * u.count
     norm_rate = total_counts / (self.exposure_time * total_counts.max())
     norm_rate_error = err_counts / (self.exposure_time *
                                     total_counts.max())
     x = self.position[:, 1]
     x_arcsec = x * self.plate_scale
     xerr = foxsi_optics_calib.plate_scale(self.pinhole_size)
     ax.errorbar(x_arcsec.value,
                 norm_rate.value,
                 yerr=norm_rate_error.value,
                 xerr=xerr.value)
     ax.set_ylabel('Normalized Rate')
     ax.set_xlabel('Position [arcsec]')
     ax.set_yscale('log')
Exemplo n.º 4
0
    def __init__(self, im, offaxis_angle, polar_angle, shift=False):
        self.im = im
        # define the wcs system
        self.w = WCS(naxis=2)
        self.w.wcs.crpix = np.unravel_index(np.argmax(self.im), self.im.shape)
        self.w.wcs.cdelt = foxsi_optics_calib.plate_scale(foxsi_optics_calib.CCD_PIXEL_PITCH).value * np.ones(2)
        self.w.wcs.crval = [0, 0]
        self.w.wcs.ctype = ["TAN", "TAN"]
        self.plate_scale = self.w.wcs.cdelt * u.arcsec
        self.polar_angle = polar_angle
        self.offaxis_angle = offaxis_angle
        pitch, yaw = (-np.sin(self.polar_angle) * self.offaxis_angle,
                      np.cos(self.polar_angle) * self.offaxis_angle)
        self.pitch = pitch
        self.yaw = yaw
        # offset is pitch then yaw
        self.offset = u.Quantity([pitch, yaw])
        if shift:
            self.w.wcs.crval += [self.yaw.to('arcsec').value,
                                 self.pitch.to('arcsec').value]

        x, y = np.meshgrid(*[np.arange(v) for v in self.im.shape]) * u.pixel
        self.xaxis, self.yaxis = self.w.wcs_pix2world(x, y, 1) * u.arcsec
Exemplo n.º 5
0
from astropy.wcs import WCS
import astropy.units as u
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.colors import LogNorm
import scipy.optimize as opt
from astropy.modeling.fitting import LevMarLSQFitter
from astropy.io import fits as pyfits
from astropy.nddata import CCDData
from copy import deepcopy
import os.path

import foxsi_optics_calib
from foxsi_optics_calib.psf import psf2d, psf_x, psf_y, calculate_best_guess_params, PSF2DModel

CCD_PLATE_SCALE = foxsi_optics_calib.plate_scale(foxsi_optics_calib.CCD_PIXEL_PITCH).value


class AndorCCDImage(CCDData):
    """
    A generic class to handle fits files created by the Andor CCD.
    This is a general class to inspect a file and
    makes no assumptions about the image. This class inherits from
    `~astropy.nddata.CCDData`.

    Parameters
    ----------
    data : `~numpy.ndarray`
        A 2d ndarray containing the image
    meta : dict-like object or None, optional
        Metadata for this object.