title: Cutout2D not centering on galaxies
body: <p>I'm running Cutout2D on a .fits image I have and despite specifying the pixel values of the centre of my object it's cutting out a completely different galaxy. My code is as follows:</p>
  
  <pre><code>from astropy.io import fits
  import numpy as np
  from astropy.table import Table
  import os
  from astropy.nddata.utils import Cutout2D
  
  def merge(list1, list2):
      #merges to lists into pairs so you can have list of corresponding coordinates matched together
      merged_list =[(list1[i], list2[i]) for i in range(0, len(list1))]
      return merged_list
  
  #read in the fits file
  insciim = fits.open('/home/myname/science_image.fits')
  indata = fits.getdata('/home/myname/science_image.fits')
  
  #Read in the header
  hdr = fits.getheader('/home/myname/science_image.fits')
  hdr["CTYPE1"] = "RA---TAN-SIP"
  hdr["CTYPE2"] = "DEC--TAN-SIP"
  
  #working from a copy to avoid overwriting the images
  sciim = np.copy(insciim)
  data = np.copy(indata)
  
  xray_sources = '/home/myname/xray_catalogue.csv' #file path to the xray sources catalgoue 
  xray_table = Table.read(xray_sources, format="ascii") #imports it as a table into python 
  
  ID = np.array(xray_table['name']) #puts the IDs into a numpy array
  ID.astype(str) #makes the array into strings
  
  x_pix = np.array(xray_table['x_pixel'])
  x_pix.astype(float)
  
  y_pix = np.array(xray_table['y_pixel'])
  y_pix.astype(float)
  
  coordinates = merge(x_pix, y_pix)
  
  size = (200, 200) #size I want the image to be in pixels
  
  cut_test = Cutout2D(data, (3480.136, 2771.585), size)
  
  img_hdu = fits.PrimaryHDU(cut_test.data, header=hdr)
  img_hdu.writeto("/home/myname/test_galaxy.fits", overwrite=True) 
  </code></pre>
  
  <p>The galaxy I want is centred on the pixel values of (3480.136, 2771.585) but when I view the cutout in DS9 its not even on my original image. IS there any way to prevent this from happening?  </p>